Question: A and B can together ?nish a work in 30 days.
They worked together for 20 days and then B left.
After another 20 days, A ?nished the remaining work.
In how many days A alone can finish the job?
Solution:
In 20 days, 2/3 part of work is done and 1/3 part is left
And A finishes 1/3 part in 20 days,
hence whole work can be done by A in 60 days
Question: A, B and C can complete a work separately in 24,
36 and 48 days respectively. They started together,
but C left after 4 days of start and A left 3 days
before the completion of the work. In how many days
will the work be completed?
Solution:
Let the work be completed in X days
(X-3)/24 + X/36 + 4/36 = 1
Solving the Eqn. X= 15
Hence, work will be completed in 15 Days
Question: If 12 men and 16 boys can do a piece of work
in 5 days and 13 men and 24 boys can do it in 4 days,
how long will 7 men and 10 boys take to do it ?
Solution:
5(12m+16b) = 4 (13m+24b)
1m=2b
From part one, 40 (24+16 ) boys can do it for 5days
Hence 24 (14+10) boys can do it for 25/3 days.
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