The reading speed of second grade students in a large city
Last updated: 12/16/2023
The reading speed of second grade students in a large city is approximately normal with a mean of 90 words per minute wpm and a standard deviation of 10 wpm Complete parts a through f c What is the probability that a random sample of 20 second grade students from the city results in a mean reading rate of more than 96 words per minute The probability is Round to four decimal places as needed Interpret this probability Select the correct choice below and fill in the answer box within your choice OA If 100 independent samples of n 20 students were chosen from this population we would expect sample s to have a sample mean reading rate of exactly 96 words per minute OB If 100 independent samples of n 20 students were chosen from this population we would expect sample s to have a sample mean reading rate of more than 96 words per minute OC If 100 independent samples of n 20 students were chosen from this population we would expect sample s to have a sample mean reading rate of less than 96 words per minute d What effect does increasing the sample size have on the probability Provide an explanation for this result OA Increasing the sample size increases the probability because o decreases as n increases increases as n increases OB Increasing the sample size increases the probability because o OC Increasing the sample size decreases the probability because o decreases as n increases O D Increasing the sample size decreases the probability because o increases as n increases e A teacher instituted a new reading program at school After 10 weeks in the program it was found that the mean reading speed of a random sample of 18 second grade students was 92 1 wpm What might you conclude based on this result Select the correct choice below and fill in the answer boxes within your choice Type integers or decimals rounded to four decimal places as needed OA A mean reading rate of 92 1 wpm is unusual since the probability of obtaining a result of 92 1 wpm or more is This means that we would expect a mean reading rate of 92 1 or higher from a population whose mean reading is 90 in of every 100 random samples of size n 18 students The new program is abundantly more effective than the old program OB A mean reading rate of 92 1 wpm is not unusual since the probability of obtaining a result of 92 1 wpm or more is This means that we would expect a mean reading rate of 92 1 or higher from a population whose mean reading rate is 90 in of every 100 random samples of size n 18 students The new program is not abundantly more effective than the old program f There is a 5 chance that the mean reading speed of a random sample of 24 second grade students will exceed what value There is a 5 chance that the mean reading speed of a random sample of 24 second grade students will exceed wpm Round to two decimal places as needed