Answer: Option A
Answer: (a)Total age of 5 members, 3 years ago = 17 × 5 = 85 years Total age of 5 members, now = (85 + 3 × 5) = 100 years Total age of 6 members, now = 17 × 6 = 102 years∴ Age of the baby = 102 – 100 = 2 years Aliter : Using Rule 17,( 't’ years before, the average age of N members of a family was 'T’ years. If during this period 'n’ children increased in the family but average age (present) remains same, then, Present age of n children = n.T – N.t )Here, t = 3, N = 5, T = 17, n = 1 Present age of baby = nT – Nt = 1 × 17 – 5 × 3 = 17 – 15 = 2 years