Question

The weights of 1,000 children average 50kg and the standard deviation is 5kg. how many

children weigh between 40kg and 50kg?



- statistics​

Answer 1

Step-by-step explanation:

Assuming the weights are normally distributed,

Given,

Total no. of children = 1000

μ(mean) = 50 kg

z = (x-μ)/σ

z(x=40)=(40-50)/5= -2

z(x=50)= 0

Area under (z= -2 to z= 0) = .9545/2

= .47725

Therefore, total number of children between 40 kg to 50 kg = .47725x1000

= 477.25

Answer 2

Given:

The weights of 1,000 children average 50kg and the standard deviation is 5kg.

To Find:

how many children weigh between 40kg and 50kg?

Solution:

Assuming the weights are normally distributed,

We know that,

Total no. of children = 1000

μ(mean) = 50 kg

z = (x-μ)/σ

z(x=40)=(40-50)/5= -2

z(x=50)= 0

Area under (z= -2 to z= 0) = .9545/2 = .47725

So,

total number of children between 40 kg to 50 kg = .47725x1000

                                                                                   = 477.25

                                                                                   = 477 (approximately)

Hence, 477 children weigh between 40kg and 50kg.