Question

Class A has 9 pupils and class B has 12 pupils.

Both classes sit the same maths test.
The mean score for class A is 35.
The mean score for both classes is 69.
What is the mean score (rounded to 1 DP) in the maths test for class B?

Answer 1

Is this from hegarty maths?

Answer 2

The mean score for class B is 103

The mean score for both classes would be defined as :

• Both classes mean = (class A mean + class B mean) / 2

Now we have :

69 = (35 + B) / 2

69 × 2 = 35 + B

138 = 35 + B

B = 138 - 35

B = 103

Hence, the mean score for class B is 103