Question

Six years ago,the average age of A,B,C and D was 30 years. When E joined them, the average of all five becomes 40 years. What is the age of E?

Answer 1

The age of E is 40

Explanation:

When E didn't join them, the average age was 30,that is six years ago. But present making 36.

But when E joined, the average age is now 40.

Answer 2

E is 56 years old

Explanation:

I assume E joined them now.

(A - 6 + B - 6 + C - 6 + D - 6)/4 = 30

(A + B + C + D + E)/5 = 40

(A + B + C + D - 24)/4 = 30

A + B + C + D - 24 = 120

A + B + C + D = 144

(A + B + C + D + E)/5 = 40

A + B + C + D + E = 200

144 + E = 200

E = 56