12 men work 8 hours per day to complete the work in 10 days. To complete the same work in 4 days, working 15 hours a day, the number of men required?  Choose the correct choice
A) 15 days  B) 12 days  C) 16 days  D) 18 days  E) 20 days

Rationale: that is , 1 work done = 12 × 8 × 10 then , 12 8 × 10 = ? × 15 × 6 ? ( i . e . no . of men required ) = 12 × 8 × 10 / 15 × 6 = 16 days c )
Answer: C