Suresh can complete a job in 15 hours. Ashutosh alone can complete the same job in 15 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 choice from the following answers
A) 4 B) 5 C) 6 D) 12 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 — 15 = 6 hours answer c"
Answer: C