Question:
A and B can do a piece of work in 10 days, B and C in 15 days and C and A in 20 days. C alone can do the work in :
A60 days
B80 days
C120 days
D30 days
Answer:
C. 120 days
Explanation:
A+B+C -------->13/2 A+B-------->6 efficiency of C---->1/2