Raj can do a piece of work in 20 days. He started the work and left after some days, when 25% work was done. After it Abhijit joined and completed it working for 10 days. In how many days Raj and Abhijit can do the complete work, working together?
Efficiency of Raj = 100 20 = 5%
Work completed by Raj = 25%
Rest work = 75%
Efficiency of Abhijit = 75 10 = 7.5%
Combined efficiency = 5 + 7.5 = 12.5%
They will complete the whole work by working together in,
= 100 12.5 = 8 days
Workspace
Working 5 hours a day, A can Complete a work in 8 days and working 6 hours a day, B can complete the same work in 10 days. Working 8 hours a day, they can jointly complete the work in
A and B together can complete a work in 3 days. They start together but after 2 days, B left the work. If the work is completed after two more days, B alone could do the work in
(A+B)’s one day’s % work = 100/3 = 33.3%
Work completed in 2 days = 66.6%
Remaining work = 33.4%;
One day’s % work of A = 33.4/2 = 16.7%;
One day’s work of B = 33.3 – 16.7 = 16.7%;
B alone can complete the work in,
= 100/16.7 = 6 days.
Workspace
If A and B together can complete a work in 18 days, A and C together in 12 days, and B and C together in 9 days, then B alone can do the work in
