The mean number of pets per household is 3.33 with standard deviation 1.6. A sample of 53 households is drawn. Find the 78th percentile of the sample mean.
A) 4.35
B) 3.50
C) 4.20
D) 2.89

Question

Quizplus · Accepted Answer

The 78th percentile of the sample mean can be found using the formula for the z-score and the standard error of the mean. The standard error is 1.6/sqrt(53). Using the z-score for the 78th percentile (approximately 0.772), the calculation gives a sample mean close to 3.50.

The Mean Number of Pets Per Household Is 3