5 years ago, the average age of A, B, C and D was 45 years. With E joining them now, the average age of all the five is 49 years. How old is E ?
5 years ago, the average age of A, B, C and D was 45 years. With E joining them now, the average age of all the five is 49 years. How old is E ?
Explanation
Given that , 5 years ago, the average age of A, B, C and D = 45
years.
Sum of A, B, C and D = 45 × 4 = 180 years
Sum of the present age of A, B, C and D = 45 × 4 + 4 × 5 = 180 + 20 = 200 years
With E joining them now, the average age of A, B, C , D and E = 49 years.
Sum of the present age of A, B, C, D and E = 49 × 5 = 245 years
∴ Present age of E = Sum of the present age of A, B, C, D and E - Sum of the present age of A, B, C and D
∴ Present age of E = (245 – 200) years = 45 years