RRB NTPC · Question 6
E and F can do a work in 10 days. If E alone can do it in 30 days, F alone can do it in _____ days. A. 15 B. 20 C. 25 D. 18
Show answer & explanation
Answer: (A) A
Explanation
E and F together do 1/10 of the work a day, and E alone does 1/30. So F does 1/10 − 1/30 = 2/30 = 1/15 a day and would take 15 days alone.