There is enough provisions for 600 men in an army camp for 25 days. If there were 250 men less, how long will the provision last? Choose the correct choice from the following answers:  A) 10 days  B) 40 days  C) 50 days  D) 60 days  E) 80 days

Rationale: "exp : we have , m 1 d 1 = m 2 d 2 600 * 25 = 250 * d 2 d 2 = 600 * 25 / 250 = 60 days . answer : d"
Answer: D