Question

The weights of 1,000 children, in average, is 55kg with standard deviation of 17kg. Suppose the weights are normally distributed, how many children weigh greater than 38kg?

Answer 1

Use Z calculations

Z(38) = (38 - 55)/17 = -1

The area to the right of the Z score is obtained as below;

( 1 - 0.15866) = 0.84134

The number of children weighing greater than 38 kg is given as;

( 0.84134 * 1000) = 841.34

Which is approximately 842 children.