question is in description

Question

using central limit therom. The mean weight of an adult is 76 kilograms with a variance of 100. If 142 adults are randomly selected, what is the probability that the sample mean would be greater than 77.4 kilograms? Round your answer to four decimal places

Answer 1

use

z=(xbar-mu)/(σ/√n)

 =(77.4-76)/(100/√142)=0.1668

 

Look up the z-score you calculated in step 3 in the z-table Subtract your z-score from 0.5 which will be the answer