Answer to Question #292952 in Statistics and Probability for secret

Question

The weights of 1,000 children, in average, is 62kg with standard deviation of 19kg. Suppose the weights are normally distributed, how many children weigh greater than 56kg?

Answer 1

Solution:

Given : mean= 62

sd = 19

formula Z= $\frac{x-mean}{sd}$

For x= 56, Z= $\frac{56-62}{19}=-0.32$

Using Z table , Pr(X>56) = Pr(Z$>$ −0.32)=Pr(Z$\le$ 0.32)=0.62552

Hence number of children = 1000$\times$ 0.62552= 625.52 approximately 626 children