Question

20 childrens are to be divided into two groups A and B of 12 and 8 children respectiveThe average marks obtained by the children of group is 85 and the average marks of all the 20 children is 80.What is the average marks of children of group B?

Answer 1

Answer:

average mark of group B = 72.5

total marks of groupB = 580

Step-by-step explanation:

Answer 2

Answer:

The average of marks obtained by children in group B is 72.5

Step-by-step explanation:

Total children in a group = 20

Since average marks of 20 children = 80

Therefore, total marks of all 20 children = 80 × 20

                                                                   = 1600

Now these children were divided into two groups A and B each having 12 and 8 children respectively.

Average marks of children in Group A = 85

So total marks of children in group A = 85×12

                                                             = 1020

Total marks obtained by children of group B = 1600 - 1020

                                                                                  = 580

Therefore, average marks of group B = $\frac{\text{Total marks of group B}}{\text{Total number of children in group B}}$

                                                               = $\frac{580}{8}$

                                                               = 72.5

Learn more questions on topic average and ratios from https://brainly.in/question/11422629