The reading speed of second grade students in a large city is approximately normal, with a mean of 89 words per minute (wpm) and a standard deviation of 10 wpm. 1. What is the probability a randomly selected student in the city will read more than 93 words per minute?
A. If 100 different students were chosen from this population, we would expect___to read less than 93 words per minute.
B. If 100 different students were chosen from this population, we would expect___to read exactly 93 words per minute.
C. If 100 different students were chosen from this population, we would expectto read more than 93 words per minute.
2. What is the probability that a random sample of 13 second grade students from the city results in a mean reading rate of more than 93 words per minute?
A. If 100 independent samples of n = 13 students were chosen from this population, we would expectsample(s) to have a sample mean reading rate of exactly 93 words per minute.
B. If 100 independent samples of n = 13 students were chosen from this population, we would expectsample(s) to have a sample mean reading rate of less than 93 words per minute.
C. If 100 independent samples of n = 13 students were chosen from this population, we would expect sample(s) to have a sample mean reading rate of more than 93 words per minute
3. What is the probability that a random sample of 26 second grade students from the city results in a mean reading rate of more than 93 words per minute?
A. If 100 independent samples of n = 26 students were chosen from this population, we would expect___sample(s) to have a sample mean reading rate of more than 93 words per minute.
B. If 100 independent samples of n = 26 students were chosen from this population, we would expect___sample(s) to have a sample mean reading rate of exactly 93 words per minute.
C. If 100 independent samples of n = 26 students were chosen from this population, we would expect___sample(s) to have a sample mean reading rate of less than 93 words per minute.
4. What effect does increasing the sample size have on the probability?
A. Increasing the sample size increases the probability because sigma^-_x increases as n increases.
B. Increasing the sample size decreases the probability because sigma^-_x decreases as n increases.
C. Increasing the sample size increases the probability because sigma^-_x decreases as n increases.
5. 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 91.5 wpm. What might you conclude based on this result?
A. A mean reading rate of wpm is not unusual since the probability of obtaining a result of wpm or more is___. This means that we would expect a mean reading rate of or higher from a population whose mean reading rate is in___of every 100 random samples of size n = 18 students. The new program is not abundantly more effective than the old program.
B. A mean reading rate of 91.5 wpm is not unusual since the probability of obtaining a result of 91.5 wpm or more is. This means that we would expect a mean reading rate of 91.5 or higher from a population whose mean reading rate is 89 inof every 100 random samples of size n = 18 students. The new program is not abundantly more effective than the old program.
6. There is a 5% chance that the mean reading speed of a random sample of 20 second grade students will exceed what value?