Five 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 ?

45 years

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