Statistics Questions
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Statistics
ProbabilityO 1 10 1 5 1 20 1 40 Probability Permutation Formula n n r A You have 5 pair of flip flops A green pair a red pair a blue pair a whi pair and a black pain If you randomly select 3 pair to take on vacation what is the probability you choose the black white and red flip flops 1 45 O 1 60 of Favorable Outcomes Total Number of Outcomes Combination Formula n n r r nC
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ProbabilityO 1 10 O 1 5 O 1 20 O 1 40 1 45 O 1 60 Permutation Formula n nPr n r A bucket contains the names of 10 people including you and your friend If 2 names are randomly selected find the probability the first name selected is yours and the second name selected is your friend s name 1 65 Combination Formula n Cr n r r
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Probability1 480 O 1 680 1 880 Permutation Formula n n r 1 1080 O 1 1280 Pr 1 1480 Probability If a lock code uses the digits 1 8 what is the probability the 4 digit code is 5555 Number of Favorable Outcomes Total Number of Outcomes Combination Formula n nC n r r
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Probability1 110 O 1 150 O 1 180 O 1 210 O 1 240 Permutation Formula n nPr n r 1 270 Total Number of Outcomes At a talent show the order in which people perform is chosen randomly If there are 7 people performing what is the probability the first three people are you then your sister then your best friend Combination Formula nC n n r r
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StatisticsA store is selling signs that read Happy Holidays The signs come in two sizes and two colors Red Green Big Small 3 4 4 2 What is the probability that a randomly selected sign is green and small Simplify any fractions
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ProbabilityPermutation Formula nPr n n r A daycare has 8 girls and 6 boys Five children are randomly selected to form a leader group What is the probability all 5 are boys O 1 1000 O 1 1001 O 1 1002 O 1 1003 O 3 1000 O 3 1001 011000 Combination Formula n nC n r r
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ProbabilityO 1 3 O 1 4 O 1 5 O 1 6 O 1 7 O 1 8 Probability 1 9 Permutation Formula nPr n n r Number of Favorable Outcomes Total Number of Outcomes A basketball team has 9 players Seven players are 13 years old anc 2 players are 12 years old If the starting 5 players is randomly selected find the probability all 5 are 13 years old Combination Formula n nCr n r r
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ProbabilityO 1 10 O 1 5 O 1 20 1 75 O 1 100 O 1 120 Probability 1 130 Permutation Formula nPr n n r Number of Favorable Outcomes Total Number of Outcomes A bag a candy contains 3 red 2 blue 4 yellow and I purple If you randomly select 3 candies from this bag what is the probability that all 3 are red Combination Formula n nC n r r
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StatisticsGive a Practical interpretation of 99 confidence Interval Ex I am 99 confident that the true mean height of all of the people in my company is between 64inches and 6 8 inches
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StatisticsGive a part estimate mean for the average height of all people in the place from which you pulled your data use all 20 of your lab Values to find this What is your point Estimate and what does this Heights nally Group 1 Groupabaiga 60 63 62 63 65 66 66 00 66 167 67 69 71 12 73 64 201 21 WEWA HATZ SIGING 72 179 You autal 74 pudine bille not aligns to
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ProbabilityGive a practical interpretation of the 99 confidence interval For example you might Say I am 99 confident that the true mean height of all of the people in my company is between 64 inches and 68 inches White a complete Sentence
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StatisticsGive Practical Intepretation of the 95 confidence interval For example You might say I am 95 confident that the true mean height of all of the people in my company is between 64 inches and 68 inches Write in complete Sentences 2 tr
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StatisticsWhich of the following represents a correct expression for the fourth linear number L4 1 1 1 1 O 1 2 3 4 O2 2 2 2 4 4 4 4
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ProbabilityConfidence interval The range of values consistent with the data that is believed to encompass the actual or true population value Sauke TA Sex M 2000 How to Repost Statistics in Medicine Chd ed Philadelphia American College of Pesicians To draw conclusions about a study population researchers use samples that they assume truly represent the population The confidence interval CI is among the most reliable indicators of the soundness of their assumption A CI is the range of values within which the population value being studied is believed to fall Cls are reported in the results section of published research and are often calculated either for mean or proportion data calculation details are beyond the scope of this article A 95 CI which is the most common level used others are 90 and 99 means that if researchers were to sample numerous times from the same population and calculate a range of estimates for these samples 95 of the intervals within the lower and upper limits of this range will include the population value To illustrate the 95 CI of a mean value say that a sample of patients with hypertension has a mean blood pressure of 120 mmHg and that the 95 CI for this mean was calculated to range from 110 to 130 mmHg This might be reported as mean 120 mmHg 95 CI 110 130 mmHg It indicates that if other samples from the same population of patients were generated and intervals for the mean blood pressure of these samples were estimated 95 of the intervals between the lower limit of 110 mmHg and the upper limit of 130 mmHg would include the true mean blood pressure of the population Notice that the width of the Cl range is a very important indicator of how reliably the sample value represents the population in question If the Cl is narrow as it is in our example of 110 130 mmHg then the upper and lower limits the sample This sample mean value is probably a more reliable estimate of the true mean value of the population than a sample mean value with a wider CI of for example 110 210 mmHg With such a wide CI the population mean could be as high as 210 mmHg which is far from the sample mean of 120 mmHg In fact a very wide CI in a study should be a red flag it indicates that more data should have been collected before any serious conclusions were drawn about the population Remember the narrower the Cl the more likely it is that the sample value represents the population value NurseONE resources ON THIS TOPIC EBSCO MEDLINE FULL TEXT ARTICLES Hildebrandt M Vervolgyl E Bender R 2009 Calculation of NNTs in RCTs with time to event outcomes A literature review BMC Medical Research Methodology 9 21 Hildebrandt M Bender R Gehrmann U Blettner M 2006 Calculating confidence intervals for impact numbers BMC Medical Research Methodology 6 32 Altman D G 1998 Confidence intervals for the number needed to treat BM Clinical Research Ed 317 7168 1309 1312 MYILIBRARY Campbell M J Machin D Walters S L 2010 Medical statistics A textbook for the health sciences 4th ed Mateo M A Kirchhoff K T Eds 2009 Research for advanced practice nurses From evidence to practice
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StatisticsHeights Group 1 60 63 65 66 66 67 70 71 72 113 Group 2 62 Mean Give A pont estimate Mc 63 for the average height of all people 64 from which you pulled your data 66 Use All 20 of your lab values to find 67 this What is your point estimate 69 and what does this mean Insert 72 74 79 Up
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StatisticsHeights Group 1 60 29352 2 67 73 Group 2 39555FO FE 63 64 66 67 69 72 74 Use Excel Spreadsheet and give a point estimate mean of the average height of all people in place I gathered My data Group 2 Start by putting the 20 Heights Group 1 2 you are working with into the blue Data Column of the Spreadsheet What is your pant intimate and what does it mean
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StatisticsA medical researcher claims that the proportion of patients receiving 200 mg of a newly developed influenza vaccine who go on to contract influenza strain X is less than the proportion of patients receiving 200 mg of last year s influenza vaccine who contract influenza strain X Of 320 patients who are given last year s vaccine 114 contract influenza strain X Of 350 patients who are given the new vaccine 112 of them contract influenza strain X Let PN be the proportion of patients receiving the newly developed vaccine and pL be the proportion of patients receiving last year s vaccine State the null and alternative hypotheses and the value of the test statistic Ho PN PL versus HA PN PL Test statistic Z 0 99
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StatisticsSuppose the scores on an exam are normally distributed with a mean u 75 points and standard deviation o 8 points Type numbers in the boxes 10 points Suppose that the top 4 of the exams will be given an A In order to be given an A an exam must earn at least what score Report your answer in whole numbers
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StatisticsColorblindness is any abnormality of the color vision system that causes a person to see colors differently than most people or to have difficulty distinguishing among certain colors www visionrx com Select one answer 10 points Colorblindness is gender based with the majority of sufferers being males Roughly 8 of white males have some form of colorblindness while the incidence among white females is only 1 random sample of 20 white males and 40 white females was chosen Let X be the number of males out of the 20 who are colorblind Let Y be the number of females out of the 40 who are colorblind Let Z be the total number of colorblind individuals in the sample males and females together Which of the following is true regarding the random variables X and Y A O Both X and Y can be well approximated by normal random variables B O Only X can be well approximated by a normal random variable C Only Y can be well approximated by a normal random variable D O Neither X nor Y can be well approximated by a normal random variable
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ProbabilityAccording to the Bureau of Labor Statistics in May 2014 the mean hourly wage of a social worker was 28 08 with a standard deviation of 1 97 Jeronica is a social worker with an hourly wage of 31 60 What is Jeronica s z score Round your answer to 2 decimal places Type numbers in the boxes 10 points
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Statisticshree random variables U V Whave distributions as shown in the graphs below Probability Probability 5 3 1 2 1 5 4 1 1 2 3 U L J 2 3 V 4 5 5 Select one 10 points
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ProbabilityAn engineering school reports that 55 of its students were male M 40 of its students were between the ages of 18 and 20 A and that 25 were both male and between the ages of 18 and 20 Select one answer 10 points What is the probability of a random student being female between the ages of 18 and 20 Assume P F P not M A O 0 15 B O 0 16 C O 0 30 D O 0 40
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ProbabilitySelect one answer According to the information that comes with a certain prescription drug when taking this drug there is a 20 chance of experiencing nausea N and a 50 chance of experiencing decreased sexual drive D The information also states that there is a 15 chance of experiencing both side effects 10 points What is the probability of experiencing neither of the side effects A O 0 10 B O 0 40 C O 0 45 D O 0 70 E O 0 85
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ProbabilitySuppose your friends have the following ice cream flavor preferences 70 of your friends like chocolate C The remaining do not like chocolate 40 of your friends sprinkles S topping The remaining do not like sprinkles 25 of your friends who like chocolate C also like sprinkles 5 Select one answer 10 phras If your friend had chocolate how likely is it that they also had sprinkles Note Some answers are rounded to 2 decimal places A O 0 10 B O 0 18 C O 0 28 D O 0 36 E O0 63
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ProbabilityA fair die is rolled 12 times Consider the following four possible outcomes i ii 526321416534 iv 112233445566 iii 666666666666 154351244645 Select one answer 10 points Which of the following is the most likely outcome i ii iii iv A O i because number of die outcomes 1 2 3 4 5 6 is equal but in a random order B ii because the number of die outcomes 1 2 3 4 5 6 is equal C O iii because the number 6 is just as likely as any other number on a die D O iv because you won t necessarily get the same number of of die outcomes 1 2 3 4 5 6 with a fair die E O They are all equally likely attempt
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ProbabilitySuppose that the handedness of the last fifteen U S presidents is as follows 40 were left handed L 47 were Democrats D If a president is left handed there is a 13 chance that the president is a Democrat S Select one answer 10 points Based on this information on the last fifteen U S presidents is being left handed independent of being a Democrat A O Yes since 0 47 is not equal to 0 13 B O No since 0 40 is not equal to 0 13 C O Yes since 0 40 0 47 is not equal to 0 13 D O No since 0 47 is not equal to 0 13
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ProbabilityIn a certain liberal arts college with about 10 000 students 40 are males If two students from this college are selected at random what is the probability that they are both males A Oo B O 0 16 C O 0 80 D O 0 64 E O 0 25 Select one answer 10 points
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ProbabilitySelect one answer An engineering school reports that 55 of its students were male M 40 of its students were 10 points between the ages of 18 and 20 A and that 25 were both male and between the ages of 18 and 20 What is the probability of a random student being a female who is not between the ages of 18 and 20 A O 0 27 B O 0 25 C O 0 30 D O 0 45
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ProbabilityThe following probabilities are based on data collected from U S adults during the National Health Interview Survey 2005 2007 Individuals are placed into a weight category based on weight height gender and age Probability Underweight A O 0 0889 B O 0 35 C O 0 254 D O 0 604 0 019 Healthy Weight 0 377 Overweight Not Obese 0 35 Select one answer 10 points Obese 0 254 Based on this data what is the probability that a randomly selected U S adult weighs more than the healthy weight range
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ProbabilityFor safety reasons four different alarm systems were installed in the vault containing the safety deposit boxes at a Beverly Hills bank Each of the four systems detects theft with a probability of 0 99 independently of the others The bank obviously is interested in the probability that when a theft occurs at least one of the four systems will detect it What is the probability that when a theft occurs at least one of the four systems will detect it A O 0 99 4 B O 0 01 4 Select one answer C 01 0 99 4 D 01 0 01 4
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StatisticsIn a recent school election at a large school we know that 45 of the students supported candidate X and the other 55 supported candidate Y Assume everyone has a strong opinion about one candidate or the other If we select 2 students at random what is the probability that they both support candidate X A OO B O 0 2025 C O 0 6975 D O 0 90 Select 10 pot
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ProbabilityIn the population 8 of males have had a kidney stone Suppose a medical researcher randomly selects two males from a large population Let A represent the event the first male has had a kidney stone Let B represent the event the second male has had a kidney stone True or false A and B are independent events A O True B Felco Select one answer 10 points
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Probabilityfair coin is tossed 12 times Which of the following outcomes i ii iii or iv is most likely i HTHTHTHTHTHT ii HTTHHTTHTHHT iii HHHHHHHHHHHH iv TTTHTHHHHTHH Select one answe 10 points A O i because there are an equal number of heads and tails B ii because there are an equal number of heads and tails but in a random order C O iii because heads are just as likely as tails D O iv because you won t necessarily get the same number of heads and tails with a fair coin E O They are all equally likely
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ProbabilitySelect one answer 10 points The CSU system reported the following probabilities for their student body in 2013 The probability of their student being a male between 17 and 19 is P A 0 11 The probability of their student being a female between 20 and 24 P B 0 30 What is P A and B given that year A O 0 033 B O 0 410 C O 0 377 D OO
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ProbabilityA six sided cube is rolled What is the probability that the number is odd or less than 4 Event A Numbers on a six sided cube are odd 1 3 5 Event B Numbers on a six sided cube are less than 4 1 2 3 A 01 2 B 02 3 C 05 6 D 01 Select one answer 10 points
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ProbabilityLet A and B be two independent events If P A 0 5 what can you say about P A B A O Cannot find it because P B is not known B O Cannot find it because P A and B is not known C O Cannot find it because both P B and P A and B are not known D O It is equal to 0 5 E O It is equal to 0 25 Select one answer 10 points
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StatisticsSelect one an 10 points Dogs are inbred for such desirable characteristics as blue eye color but an unfortunate by product of such inbreeding can be the emergence of characteristics such as deafness A 1992 study of Dalmatians by Strain and others as reported in The Dalmatians Dilemma found the following i ii 31 of all Dalmatians have blue eyes 38 of all Dalmatians are deaf iii If a Dalmatian has blue eyes there is a 42 chance that it is deaf Based on the results of this study is having blue eyes independent of being deaf A O Yes since 0 38 is not equal to 0 42 B O Yes since 0 31 0 38 is not equal to 0 42 C O No since 0 31 is not equal to 0 42 D O No since 0 38 is not equal to 0 42
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StatisticsA local city council s study found that the correlation between number of liquor stores in a neighborhood and neighborhood crime rates across all city neighborhoods was r 0 88 Select one answer 10 points Which one of the following statements is true A O Population is a possible lurking variable in this scenario since areas that are more densely populated are more likely to have higher crime rates B O Closing liquor stores in a neighborhood will help to reduce the crime rate of that neighborhood C O As the number of liquor stores increase the crime rate will increase in that neighborhood D O There is a pretty strong positive linear relationship between number of liquor stores and crime rates
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Statistics1 12 oints eBook Print References April 1 Tanner invested 125 000 cash along with office equipment valued at 30 000 in the company in exchange for common stock April 2 April 3 April 6 April 9 April 13 April 19 The company prepaid 7 200 cash for 12 months rent for office space Hint Debit Prepaid Rent for 7 200 The company made credit purchases for 15 000 in office equipment and 3 000 in office supplies Payment is due within 10 days The company completed services for a client and immediately received 2 000 cash The company completed a 10 000 project for a client who must pay within 30 days The company paid 18 000 cash to settle the account payable created on April 3 The company paid 6 000 cash for the premium on a 12 month prepaid insurance policy Hint Debit Prepaid Insurance for 6 000 The company received 8 000 cash as partial payment for the work completed on April 9 The company completed work for another client for 2 640 on credit The company paid a 6 200 cash dividend April 22 April 25 April 28 April 29 The company purchased 1 000 of additional office supplies on credit April 30 The company paid 700 cash for this month s utility bill Required 1 Prepare general journal entries to record these transactions using the following titles Cash 101 Accounts Receivable 106 Office Supplies 124 Prepaid Insurance 128 Prepaid Rent 131 Office Equipment 163 Accounts Payable 201 Common Stock 307 Dividends 319 Services Revenue 403 and Utilities Expense 690 2 Post the journal entries from part 1 to the ledger accounts 3 Prepare a trial balance as of April 30 Complete this question by entering your answers in the tabs below Required 1 Required 2 Required 3 Check my work
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Statisticskipped eBook Print eferences Business transactions completed by Hannah Venedict during the month of September are as follows a Venedict invested 84 000 cash along with office equipment valued at 24 000 in a new business named HV Consulting in exchange for common stock b The company purchased land valued at 45 000 and a building valued at 155 000 The purchase is paid with 30 000 cash and a note payable for 170 000 c The company purchased 1 700 of office supplies on credit d Venedict invested an automobile in the company in exchange for more common stock The automobile has a value of 16 800 e The company purchased 5 600 of additional office equipment on credit f The company paid 1 700 cash salary to an assistant g The company provided services to a client and collected 7 800 cash h The company paid 640 cash for this month s utilities i The company paid 1 700 cash to settle the account payable created in transaction c J The company purchased 20 100 of new office equipment by paying 20 100 cash k The company completed 6 000 of services on credit for a client who must pay within 30 days 1 The company paid 1 700 cash salary to an assistant m The company received 3 000 cash in partial payment on the receivable created in transaction k n The company paid a 2 600 cash dividend Required 1 Prepare general journal entries to record these transactions using the following titles Cash 101 Accounts Receivable 106 Office Supplies 108 Office Equipment 163 Automobiles 164 Building 170 Land 172 Accounts Payable 201 Notes Payable 250 Common Stock 307 Dividends 319 Consulting Revenue 403 Salaries Expense 601 and Utilities Expense 602 2 Post the journal entries from part 1 to the ledger accounts 3 Prepare a trial balance as of the end of September
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StatisticsGraph the line with the equation y x 1 10 9 8 7 6 5 4 3 2 1 10 9 8 7 6 5 4 3 2 1 1 2 y 3 4 567 co 5 6 8 1 2 3 4 5 6 7 8 9 10
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StatisticsEach credit score number has a matching rating What credit rating does a score of 780 represent Choose 1 answer A B good very good
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Statistics10 1 5attle 6 10 12 a What is the median Interpret this value in the situation 2 One 500 13 14 8 18 19 a What is the mean b What is the MAD mber of errors on a typing test 132 b What is the IQR 2 The data set represents the heights in centimeters of ten model bridges made for an engineering competition 14 8 134 9 16 16 9 16 3 Describe the shape of the distribution shown in the dot plot The dot plot displays th golf scores from a golf tournament a dot plot the distributor 10 138 136 golf score strokes 16 10 140 18
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StatisticsVictoria Gallinaro Yesterday As I will be taking a lot of blood in my time I thought that a hypothesis on which blood type is most popular in the world would be a relevant discussion post My hypothesis is that about 30 of the population have a blood type of O positive And with a study I found stating that about every 1 in 3 people have o positive blood that hypothesis could be deemed true based off the study alone At the 5 significance rate I would fail to reject the null hypothesis as a 21 percent p value is much greater than the 5 If by some chance the two tailed test p value came back to be less than 5 percent I would have examined further and read into my article that I found to see why there was such a disparity between the study and what is actually that case when it comes to blood type The article in question is from the Red Cross which is why my confidence in my hypothesis was so strong My conclusion is that out of all of the people I take blood for more of the population will have type O positive blood Works Cited Cross R 2023 March 15 O blood type Type O Blood https www redcrossblood org donate blood blood types o blood type html Reply O Summary
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StatisticsData Set 2 Frass and Predators A further experiment was conducted to test whether predators could be attracted by the smell of frass Artificial shelters similar to those of the caterpillars were placed with either 6 frass pellets or 6 beads designed to look like frass Predator wasps were introduced to the containers Each wasp had to individually choose between larva in a shelter with its frass and a larva in a shelter with pellets to visually imitate the frass but not the smell The percentage of time spent by each wasp at each container was recorded 100 Porcontago 75 50 25 4 What CLAIM can be made from the collected data 5 What is the independent variable Visits What is the dependent variable 6 Summarize the EVIDENCE that supports the claim Time Bead Shelter Frass Shelter 7 Consider both data sets Answer the experimental question and use REASONING in the analysis with regard to the behavior of flinging frass 8 Extension Another hypothesis suggests that frass flinging occurs because waste reduces overall fitness and
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StatisticsShooting the Poop CER Adapted from NSTA V Question Why do caterpillars fling their frass Experimental design Caterpillars were raised in individual containers where they could build shelters One had a clean treatment where frass caterpillar poop was removed daily from the container The other had a frassy treatment which allowed frass to accumulate in the container throughout development She measured the mass of 61 caterpillars in Year 1 30 in each treatment and 50 caterpillars in Year 2 25 in each treatment Average Caterpillar Mass 1000 750 500 250 0 15 5 Year 1 frassy clean 11 15 2 What is the independent variable 11 What is the dependent variable 20 25 H1 1 What CLAIM can be made from the collected data Year 2 frassy clean Pupae Caterpillar Age 3 Summarize the EVIDENCE that supports the claim 5 11 15 20 HA ll 25 31 Pupae HA
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StatisticsA magazine regularly tested products and gave the reviews to its customers In one of its reviews it tested two types of batteries and claimed that the batteries from Company A outperformed the batteries from Company B A representative from Company B asked for the exact data from the study The author of the article told the representative from Company B that in 200 tests a battery from Company A outperformed a battery from Company B in 108 of the tests Company B decided to sue the magazine claiming that the results were not significantly different from 50 and that the magazine was slandering its good name Use Excel to test whether the true proportion of times that Company A s batteries outperformed Company B s batteries is different from 0 5 Identify the p value rounding to three decimal places Round the test statistic to two decimal places Provide your answer below p value
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StatisticsSteve listens to his favorite streaming music service when he works out He wonders whether the service s algorithm does a good job of finding random songs that he will like more often than not To test this he listens to 50 songs chosen by the service at random and finds that he likes 32 of them Use Excel to test whether Steve will like a randomly selected song more often than not and then draw a conclusion in the context of the problem Use a 0 05 Select the correct answer below O Reject the null hypothesis There is sufficient evidence to conclude that Steve will like a randomly selected song more often than not Reject the null hypothesis There is insufficient evidence to conclude that Steve will like a randomly selected song more often than not Fail to reject the null hypothesis There is sufficient evidence to conclude that Steve will like a randomly selected song more often than not Fail to reject the null hypothesis There is insufficient evidence to conclude that Steve will like a randomly selected song more often than not
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ProbabilityDmitry suspects that his friend is using a weighted die for board games To test his theory he wants to see whether the proportion of odd numbers is different from 50 He rolled the die 40 times and got an odd number 14 times Dmitry conducts a one proportion hypothesis test at the 5 significance level to test whether the true proportion of odds is different from 50 a Ho p 0 5 H p0 5 which is a two tailed test b Use Excel to test whether the true proportion of odds is different from 50 Identify the test statistic z and p value from the Excel output rounding to three decimal places Provide your answer below test statistic p value 41
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ProbabilityDmitry suspected that his friend is using a weighted die for board games To test his theory he wants to see whether the proportion of odd numbers is different from 50 He rolled the die 40 times and got an odd number 14 times Dmitry conducts a one proportion hypothesis test at the 5 significance level to test whether the true proportion of odds is different from 50 a Which answer choice shows the correct null and alternative hypotheses for this test Select the correct answer below O Ho p 0 35 Ha p 0 35 which is a right tailed test O Ho p 0 5 Hap 0 5 which is a left tailed test O Ho p 0 35 Ha p 0 35 which is a two tailed test O Ho p 0 5 Ha p0 5 which is a two tailed test II