A study of peach trees showed that the average number of peaches per tree was 1000. The standard deviation of the population is 150. A scientist wishes to find the 98% confidence interval for the mean
Number of peaches per tree. How many trees does she need to sample to be accurate within 20 peaches
Per tree?
A) 57
B) 217
C) 257
D) 306

Question

Quizplus · Accepted Answer

To find the sample size (n) needed for a specific margin of error (E) in a confidence interval, use the formula: n = (Z*σ/E)^2. For a 98% confidence level, Z is approximately 2.33. Plugging in the values: n = (2.33*150/20)^2 ≈ 306.

A Study of Peach Trees Showed That the Average Number