NextMockSearch exams, e.g. SSC CGL, UPPSC, Lekhpal
Railways PYQCBT 1 2016

RRB NTPC · Question 76

Manish, Mukesh and Sachin are Accountants. Mukesh can file a return in 5 hours and Sachin in 4 hours alone. All three together can do it in 2 hours. In what time (in hrs.) will Manish do the work? A. 15 B. 20 C. 17 D. 10

  1. C

  2. B

  3. A

  4. D

Show answer & explanation

Answer: (B) B

Explanation

All three together do 1/2 of the work per hour; Mukesh does 1/5 and Sachin 1/4. Manish's rate = 1/2 − 1/5 − 1/4 = (10 − 4 − 5)/20 = 1/20, so he alone takes 20 hours.