Question

g In a sample of 30 people, the average cost of a latte is $4.01. The standard deviation for the sample is $1.85. What is the margin of error for a 99% confidence interval

Answer 1

Margin of Error = ± 0.871

Explanation:

The formula for Margin of Error = ± z × Standard deviation /√n

Where

Standard deviation = $1.85

n = Random number of samples = 30

z = z score for 99% confidence interval = 2.58

Hence,

Margin of Error = ± 2.58 × 1.85/√30

Margin of Error = ± 0.871426589

Approximately = ± 0.871