Question

The average age of a group of nine children is 7 years.

Q: Answer-The average age of a group of nine children is 7 years. From the group, three children, whose ages w...

Initial sum of the ages of 9 children 7 x 9 63 years Ages of the children leaving 7 3 10 years, 7 2 9 years, and 7 4 11 years, Sum of the ages of the children leaving the group 10 9 11 30 years Sum of the ages after three children left 63 30 33 years Sum of the ages of 7 new children 7 2 x 7 63 years Total sum of the ages with new children 33 63 96 years Number of children now 9 3 6 12 years New average age 9612 8 years

From the group, three children, whose ages were 3 years more, 2 years more, and 4 years more than the average age, left. Six new children, whose average age is 2 years more than the given average age, join the group. Find the new average age.

A 10.5 years

B 9 years

C 8.5 years

D 13 years

E 8 years

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