# Question: Suppose for a random sample of 1001 Americans age 15

Suppose for a random sample of 1001 Americans age 15 or older, the mean amount of time spent eating or drinking per day is 1.22 hours with a standard deviation of 0.65 hour.

(a) A histogram of time spent eating and drinking each day is skewed right. Use this result to explain why a large sample size is needed to construct a conﬁdence interval for the mean time spent eating and drinking each day.

(b) In 2010, there were over 200 million Americans age 15 or older.Explain why this,along with the fact that the data were obtained using a random sample, satisﬁes the requirements for constructing a conﬁdence interval.

(c) Determine and interpret a 95% conﬁdence interval for the mean amount of time Americans age 15 or older spend eating and drinking each day.

(d) Could the interval be used to estimate the mean amount of time a 9-year-old American spends eating and drinking each day? Explain.

(a) A histogram of time spent eating and drinking each day is skewed right. Use this result to explain why a large sample size is needed to construct a conﬁdence interval for the mean time spent eating and drinking each day.

(b) In 2010, there were over 200 million Americans age 15 or older.Explain why this,along with the fact that the data were obtained using a random sample, satisﬁes the requirements for constructing a conﬁdence interval.

(c) Determine and interpret a 95% conﬁdence interval for the mean amount of time Americans age 15 or older spend eating and drinking each day.

(d) Could the interval be used to estimate the mean amount of time a 9-year-old American spends eating and drinking each day? Explain.

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