Six years ago, the average of the ages of Ravi, Mohan and Govind was 32 years. If Shyam joins them now, the average of the ages of all four of them is 36 years. The present age of Shyam is:

35 years 32 years 40 years 30 years

30 years

Sum of Present age of Ravi , Mohan and Govind = 3 × 32 + 3×6  = 114 years Sum of present age of Ravi , Mohan , Govind & Shyam = 36 × 4 = 144 years Age of Shyam = 144 - 114 = 30 years