Question

The weights for a group of 18-month- old girls are normally distributed with a mean of 24.5 pounds and a standard deviation of 2.8 pounds. Use the given table to find the percentage of 18 -month-old girls who weigh more than 27.3 pounds. _ % of 18-month-old girls in the sample weigh more than 27.3 pounds.

Answer 1

Remember that

z =(x - μ)/σ

where

μ=24.5 pounds

σ=2.8 pounds

so

For x=27.3 pounds

Find out the value of z

z=(27.3-24.5)/2.8

z=1

Looking at the given tables

The probability is equal to (100-84.13)=15.87

therefore

The answer is 15.87%