In a random sample of 28 families, the average weekly food expense was $95.60 with a standard deviation of $22.50. Determine whether a normal distribution or a t-distribution should be used or whether neither of these
Can be used to construct a confidence interval. Assume the distribution of weekly food expenses is normally
Shaped.
A)Use the t-distribution.
B)Use normal distribution.
C)Cannot use normal distribution or t-distribution.

Question

Quizplus · Accepted Answer

Since the sample size is less than 30 and the population standard deviation is unknown, a t-distribution should be used to construct the confidence interval, assuming the distribution of weekly food expenses is normally shaped.

In a Random Sample of 28 Families, the Average Weekly