A contractor undertakes to built a walls in 50 days. He employs 40 peoples for the same. However after 25 days he finds that only 40% of the work is complete. How many more man need to be employed to complete the work in time?
Answers:	A) 60	B) 30	C) 35	D) 20	E) none of these

Rationale: "40 men complete 0.4 work in 25 days . applying the work rule , m 1 × d 1 × w 2 = m 2 × d 2 × w 1 we have , 40 × 25 × 0.6 = m 2 × 25 × 0.4 or m 2 = 40 × 25 × 0.6 / 25 × 0.4 = 60 men answera"
Answer: A