Probability Questions and Answers

Suppose that North Carolina decides to randomly test high school football players for steroid use: North Carolina plans to test 50 of these athletes by randomly choosing 3 from each team. In the state of North Carolina there are 45 teams with 30 players on each team. Is this a simple random sample? How do you know? Yes, because the football players were chosen at random. Yes, if you put all football players' names in a hat and randomly chose 50 players you could get the answer described.

17) A lottery offers one $1000 prize, one $500 prize, and four $100 prizes. One thousand tickets are sold at $3.00 each. Find the expectation if a person buys one ticket. A) -$1.40 B) $1.60 C) $1.90 D) -$1.10

A set of exam scores is normally distributed with a mean = 74 and standard deviation = 8. Use the Empirical Rule to complete the following sentences. 68% of the scores are between and 95% of the scores are between and 99.7% of the scores are between and

To determine how American college students feel about commuting, 100 students at a private university were randomly chosen by selecting 50 men and 50 women to participate. They were asked how far they commute each day (in minutes) to campus. The results of this survey are unreliable primarily because of the absence of a control group voluntary response bias response bias sampling bias None of the above

At the Stop 'n Go tune-up and brake shop, the manager has found that an SUV will require a tune-up with a probability of 0.6, a brake job with a probability of 0.1 and both with a probability of 0.02. What is the probability that an SUV requires either a tune-up or a brake job? A) 0.58 B) 0.32 C) 0.7 D) 0.68

Eleven of the 50 digital video recorders (DVRs) in an inventory are known to be defective. What is the probability you randomly select an item that is not defective? The probability is (Do not round.)

An experiment involves selecting a numbered chip, some black and some white, from a bag of chips. The probability of selecting a black chip with an odd number is 1/5. The probability of selecting a black chip is 2/3. (3 points) What is the probability of selecting a chip with an odd number given that the chip is black? Calculate P(BIA) showing all work (no work = no points)

A coin with heads and tails is flipped and a spinner with 4 equal sections (1, 2, 3, 4) is spun once. See section 6.02 for help (3 points) (a) Show all your possible outcomes. (1 points) Answer: Double Click to write in Paint

Five people are randomly selected from a group of 7 men and 3 women to form a committee. What is the probability that the committee will have two women on it?

A company sends 15 representatives to an industry conference, 10 women and 5 men. Only 8 representatives will be given the chance to make presentations. What is the probability that all the representatives that make presentations will be women?

Evaluate the following probabilities based on the standard normal distribution: Round all answers to at least 3 decimal places. a. P(z < 2.38) = b. P(z > 2.01) = c. P(-2.23<z < 0.08) d. P(z > 1.01) =

Complete the following_statement: According to the empirical rule for a normal distribution, approximately of the data values will lie within three standard deviations on each side of the mean. A. 99.7% B. 95% C. 92.5% D. 68% E. 75%

Identify the sampling technique used to obtain a sample. A deck of cards is shuffled and a card is drawn at random. A. Cluster sampling B. Random sampling C. Systematic sampling D. Stratified sampling

Write out the sample space and assume each outcome is equally likely. Then give the probability of the requested outcomes. A man is shopping for a new patio umbrella. There is a 10-foot and a 14-foot model, and each is available in black, forest green, and brown. (a) He buys a 14-foot forest green umbrella. (b) He buys a 10-foot umbrella. (c) He buys a black-colored umbrella. Write out the sample space. Choose the correct answer below. A. {(10-foot, black), (10-foot, forest green), (10-foot, brown), (14-foot, black), (14-foot, forest green), (14-foot, brown)} B. Ø C. {(10-foot, black), (10-foot, forest green), (10-foot, brown), (14-foot, black), (14-foot, forest green)} D. {(10-foot, 14-foot), (black, forest green), (forest green, brown), (black, brown)} (a) He buys a 14-foot forest green umbrella. The probability is (Type an integer or a simplified fraction.) (b) He buys a 10-foot umbrella. The probability is (Type an integer or a simplified fraction.) (c) He buys a black-colored umbrella. The probability is (Type an integer or a simplified fraction.)

For which of the following experiments would the results show in an experimental probability of 3/5? A A coin is flipped 10 times. It lands on heads 6 times. B Two numbers cubes are rolled 25 times. The sum of 6 appears 9 times. C A spinner with three equal sections lands on the number five. D A number is randomly selected from a set of ten numbers, 1 to 10. The number three is selected on the fifth draw.

A game show contestant is offered the option of receiving a computer system worth $2500 or accepting a chance to win either a luxury vacation worth $5200 or a boat worth $7100. If the second option is chosen the contestant's probabilities of winning the vacation or the boat are 0.20 and 0.15, respectively. If the contestant were to turn down the computer system and go for one of the other prizes, what would be the expected winnings? The expected winnings are $

Jordan must complete summer assignments for her language arts, science, and history classes. She is having trouble deciding which assignment to complete first. Which of the following best describes a method of assuring that each assignment has a fair chance of being selected to be completed first? OA. Draw a card from an ordinary deck of 52 cards. If the drawn card is a heart, choose language arts. If the drawn card is a diamond, choose science. If the drawn card is a club, choose history. If the drawn card is a spade, draw again. OB. Roll an ordinary die. If the die lands on 1, choose language arts. If the die lands on 2, choose science. If the die lands on any other number, choose history. OC. Flip two fair coins. If both coins land on heads, choose language arts. If both coins land on tails, choose science. If one coin lands on heads and the other lands on tails, choose history. COD. Using a random number generator, generate an integer. If the number is positive, choose language arts. If the number is negative, choose science. If the number is 0. choose history.

The city of Raleigh has 11200 registered voters. There are two candidates for city council in an upcoming election: Brown and Feliz. The day before the election, a telephone poll of 550 randomly selected registered voters was conducted. 237 said they'd vote for Brown, 267 said they'd vote for Feliz, and 46 were undecided. Describe the sample for this survey. All citizens of Raleigh O All registered voters in Raleigh O All registered voters with telephones in Raleigh O The 550 voters surveyed O The 237 voters who said they'd vote for Brown O None of the above

A survey of athletes at a high school is conducted, and the following facts are discovered: 41% of the athletes are football players, 18% are basketball players, and 10% of the athletes play both football and basketball. An athlete is chosen at random from the high school: what is the probability that they are either a football player or a basketball player? Enter your answer as a percentage.

Work the following problem using the Target Variable Strategy taught in the Pyrenees Probability Tutor. You must show all work, including any other probabilities you determine, and the principle you use to derive each probability, to receive full or partial credit. Please type your answer in the textbox below OR attach a file (PDF or image) with your answer for this question. X and Y are two events with p(X) = 0.3. p(Y) = 0.7, and p(~ Xn~Y) = 0.4. Find p(X n Y).

3You are taking a multiple-choice test that has 6 questions. Each questios has four answer choices, with one correct answer per question. If you select one of these three choices for each question and leave nothing blank, in how many ways can answer the questions.

A factory produces plate glass with a mean thickness of 4mm and a standard deviation of 1.1 mm. A simple random sample of 100 sheets of glass is to be measured, and the mean thickness of the 100 sheets is to be computed. What is the probability that the average thickness of the 100 sheets is less than 4.03 mm?

Suppose the odds in favor of my being nice are given as 11:15. 1. What is the probability that the next time we meet I will be nice? give your result as a reduced fraction 2. What are the odds against my being nice the next time we meet?

A party platter contains 38 cupcakes: 12 chocolate, 11 yellow, and 15 lemon. You randomly select one cupcake, eat it, then randomly select another cupcake. Find the probability of selecting from the platter a chocolate cupcake and then a yellow cupcake.

A NHL players' labor negotiation committee is to be selected from twelve player representatives from the Eastern Conference and eleven from the Western Conference. Find the probability of selecting six Eastern Conference representatives and three Western Conference representatives.

In a class of 59 students, 19 have black hair, 17 have brown hair, 17 have blonde hair, and 6 have red hair. If one student is selected at random to put a problem on the board, find the odds against selecting a student with red hair.

Determine the number of possible outcomes for each experiment. (a) Flipping a coin outcomes (b) Rolling a standard die outcomes (c) Choosing a letter from the alphabet outcomes

A bag holds 30 marbles. The odds of randomly selecting a blue marble is 1 to 5. How many blue marbles are in the bag? a) 1 b) 5 c) 6 d) 30

The test statistic of z= -2.01 is obtained when testing the claim that p< 7/9. This is a left-tailed test. Using a 0.01 significance level, complete parts (a) and (b). a. Find the critical value(s). Select the correct choice below and fill in the answer box(es) within your choice. A. There is one critical value; the critical value is B. There are two critical values; the lower critical value is and the upper critical value is .

Every cereal box has a gift inside, but you cannot tell from the outside what the gift is. The store manager assures you that 15 of the 62 boxes on the shelf have the secret decoder ring. The other 47 boxes on the shelf have a different gift inside. If you randomly select two boxes of cereal from the shelf to purchase, what is the probability that BOTH of them have the secret decoder ring?

During the course of the basketball season, Lisa made 80 of 100 free throws. When we say that the probability of her making a free throw is 80% what type of probability are we stating? a) a theoretical probability b) a relative frequency probability c) a subjective probability d) none of the above

Dave's wardrobe contains 30 T-shirts, of which 5 are gray. Dave selects a T-shirt at random. What is the probability that Dave will select a gray T- shirt? Enter a reduced fraction What are the odds in favor of Dave selecting a gray T-shirt?

If the probability of the Seattle Mariners winning the World Series is 1/36 What are the odds of the Mariners winning the World Series? What is the probability of the Mariners not winning? What are the odds of the Mariners not winning?

There is a rack of 15 billiard balls. Balls numbered 1 through 8 are solid-colored. Balls numbered 9 through 15 contain stripes. If one ball is selected at random, determine the odds for it being striped. The odds are (Type whole numbers. Simplify your answer.)

You are pulling from a bag containing 7 blue marbles, 10 black marbles, 5 green marbles, and 2 yellow marbles. What is the probability as a decimal of pulling a blue marble? Round your answer to the nearest hundredth.

You pick 6 digits (0-9) at random without replacement, and write them in the order picked. What is the probability that you have written the first 6 digits of your phone number? Assume there are no repeats of digits in your phone number. Give your answer as a fraction.

Chad buys a bag of cookies that contains 6 chocolate chip cookies, 6 peanut butter cookies, 6 sugar cookies and 9 oatmeal cookies. What is the probability that Chad reaches in the bag and randomly selects a chocolate chip cookie from the bag, eats it, then reaches back in the bag and randomly selects a peanut butter cookie? Give your answer as a fraction, or accurate to at least 4 decimal places.

Suppose a jar contains 19 red marbles and 15 blue marbles. If you reach in the jar and pull out 2 marbles at random at the same time, find the probability that both are red.

Suppose that a certain college class contains 54 students. Of these, 30 are juniors, 32 are history majors, and 5 are neither. A student is selected at random from the class. (a) What is the probability that the student is both a junior and a history major? (b) Given that the student selected is a history major, what is the probability that she is also a junior? Write your responses as fractions. (a) 0 (b) 0 X

The Welcher Adult Intelligence Test Scale is composed of a number of subtests. On one subtest, the raw scores have a mean of 35 and a standard deviation of 6. Assuming these raw scores form a normal distribution: a) What number represents the 65th percentile (what number separates the lower 65% of the distribution)? b) What number represents the 90th percentile? c) What is the probability of getting a raw score between 28 and 38? d) What is the probability of getting a raw score between 41 and 44?

Suppose you read on the back of a lottery ticket that the chances of winning a prize are 1 out of 10. Select the best interpretation. You should win once out of the next 10 times but it is not for sure. You will win at least once out of the next 10 times you buy a ticket. You will win at most once out of the next 10 times you buy a ticket. You will win exactly once out of the next 10 times you buy a ticket.

When a fair die is thrown, the probability of obtaining a "6" is 1/6. Charles throws such a die repeatedly. (a)Calculate the probability that (i) he throws at least two "6"s in his first ten throws; (ii) he throws his first "6" on his fifth throw; (b) On which throw is he most likely to throw his first "6"?

A game company created a little plastic dog that can be tossed in the air. It can land either with all four feet on the ground, lying on its back, lying on its right side, or lying on its left side. However, the company does not know the probability of each of these outcomes. They want to estimate the probabilities. Which of the following methods is most appropriate? Since there are four possible outcomes, assign a probability of 1/4 to each outcome. Toss the plastic dog many times and see what percent of the time each outcome occurs. Simulate the data using a model that has four equally likely outcomes. None of the above.

Suppose that 11% of people own dogs. If you pick two people at random, what is the probability that they both own a dog? Give your answer as a decimal (to at least 3 places) or fraction

a. Find the probability that in a sample of 7 customers, none of the 7 will order a nonalcoholic beverage. Probability b. Find the probability that in a sample of 7 customers, at least 4 will order a nonalcoholic beverage. Probability c. Find the probability that in a sample of 7 customers, fewer than 5 will order a nonalcoholic beverage.

You pick 5 digits (0-9) at random without replacement, and write them in the order picked. What is the probability that you have written the first 5 digits of your phone number? Assume there are no repeats of digits in your phone number. Give your answer as a fraction.

The Hiking Club plans to go camping in a State park where the probability of rain on any given day is 58%. What is the probability that it will rain on exactly zero of the three days they are there? Round your answer to the nearest thousandth.

1. Jamila has two urns A and B. Urn A contains 17 red marbles and 3 green marbles. Um B contains 6 red marbles and 4 green marbles. Jamila rolls a balanced die. If the die lands on 4, Jamila picks from Um A, otherwise she picks from Um B. As a fraction in lowest terms, what is the probability of Jamila picking a red marble? 17/20

A bag contains 8 red, 4 white, and 5 blue marbles. Find the probability of picking 3 blue marbles if each marble is returned to the bag before the next marble is picked. 5/17 125/4913 1/4913 3/5

A die is rolled twice. What is the probability of showing a 5 on both rolls?