The time taken by A and B to finish a work is 120 days. B and C can finish the work in 72 days and A and C can do it in 90 days. When working together, 80% of the work is finished in:
1
48
2
64
3
80
4
60
The time taken by A and B to finish a work is 120 days. B and C can finish the work in 72 days and A and C can do it in 90 days. When working together, 80% of the work is finished in: