2. According to a report from a business intelligence company, smartphone owners are using an
average of 17 apps per month. Assume that number of apps used per month by smartphone
owners is nommally distributed and that the standard deviation is 4. Complete parts (a) through
(d) below. a. If you select a random sample of 36 smartphone owners, what is the probability that
the sample mean is between 16.5 and 17.5 ? (Round to three decimal places as needed.) b. If you
select a random sample of 36 smartphone owners, what is the probability that the sample mean is
between 16 and 17 ? (Round to three decimal places as needed.) c. If you select a random sample
of 144 smartphone owners, what is the probability that the sample mean is between 16.5 and
17.5 ? (Round to three decimal places as needed.) d. Explain the difference in the results of (a)
and (c). The sample size in (c) is greater than the sample size in (a), so the standard error of the
mean (or the standard deviation of the sampling distribution) in (c) is (1) than in (a). As the
standard error (2) values become more concentrated around the mean. Therefore, the probability
that the sample mean will fall close to the population mean will always (3) when the sample size
increases. (1) less (2) decreases, (3) decrease increases. increase.
IGNOU MSCCFT and PGDCFT Exam Question Pattern: MCFT003 Counselling and Family...
2. According to a report from a business intelligence company, smartp.pdf
1. 2. According to a report from a business intelligence company, smartphone owners are using an
average of 17 apps per month. Assume that number of apps used per month by smartphone
owners is nommally distributed and that the standard deviation is 4. Complete parts (a) through
(d) below. a. If you select a random sample of 36 smartphone owners, what is the probability that
the sample mean is between 16.5 and 17.5 ? (Round to three decimal places as needed.) b. If you
select a random sample of 36 smartphone owners, what is the probability that the sample mean is
between 16 and 17 ? (Round to three decimal places as needed.) c. If you select a random sample
of 144 smartphone owners, what is the probability that the sample mean is between 16.5 and
17.5 ? (Round to three decimal places as needed.) d. Explain the difference in the results of (a)
and (c). The sample size in (c) is greater than the sample size in (a), so the standard error of the
mean (or the standard deviation of the sampling distribution) in (c) is (1) than in (a). As the
standard error (2) values become more concentrated around the mean. Therefore, the probability
that the sample mean will fall close to the population mean will always (3) when the sample size
increases. (1) less (2) decreases, (3) decrease increases. increase
