A. 10 days
B. 12 days
C. 8 days
D. 9 days
Part of work completed by C in 1 day = 1/12 Part of work completed by D in 1 day = 1/15 Part of work completed by C in 4 days
= 1/3 Work remaining = 2/3 Time taken by D to complete the work
= (2/3)÷(1/15) = 10 days
Correct Answer: A. 10 days ✔
Last Updated: February 07, 2020