U, V and W together can complete a work in 10 days. If U alone can complete the work in 20 days and V alone can complete the work in 30 days, then in how many days W alone can complete the work?

U, V and W together can complete a work in 10 days. If U alone can com

1.	U, V and W together can complete a work in 10 days. If U alone can complete the work in 20 days and V alone can complete the work in 30 days, then in how many days W alone can complete the work?
A.	30
B.	40
C.	60
D.	80
Answer» D. 80