Suresh can complete a job in 15 hours. Ashutosh alone can complete the same job in 25 hours. Suresh works for 9 hours and then the remaining job is completed by Ashutosh. How many hours will it take Ashutosh to complete the remaining job alone? Choose the correct answer:  A) 4  B) 5  C) 6  D) 10  E) none of these

Rationale: "the part of job that suresh completes in 9 hours = 9 â  „ 15 = 3 â  „ 5 remaining job = 1 - 3 â  „ 5 = 2 â  „ 5 remaining job can be done by ashutosh in 2 â  „ 5 ã — 25 = 10 hours answer d"
Answer: D