Answer:
7.1
Explanation:
6 children with an average age of 5 = 6*5 = 30 so the sum of their ages is 30
20 - 6 = 14
14 children have an average age of 8 14*8 =112 so the sum of their ages is 112
Add the two sums
30+112 = 142
Divide by the total number of children
142/20 =7.1
The average age of all the 20 children is 7.1