9. A can do a piece of work in 20 days and B can do the same piece of work in 30 days. They work together for a few days and then B goes away. If A finishes the remaining work in 4 days, how long do they work together?
Answers
Answered by
0
Step-by-step explanation:
Work done by A in 4 days = 4/20 = 1/5
Work done by A and B together = 4/5
Work done by A and B in 1 day = 1/20 + 1/30 = 1/12
A and B work together for (4/5 )/(1/12) = 48/5
= 9 3/5;days.
Similar questions