2. 10 days.
Problems on Time and Work:
1. A can do a piece of work in 20 days. He works at it for 5 days and then B finished it in 30 days. How long will they together take to complete the work?
Solution:
A’s 5 days of work = 5(1/20) = 1/4
Remaining work to be done by B in 30 days is 1-1/4 = 3/4.
Whole work will be done by B is (30*4/3) = 40 days.
Their 1 day’s work = 1/20 +1/40 = 3/40.
Together they can complete in 40/3 = 13(1/3) days.
2. A and B together can do a piece of work in 30 days. A having worked for 16 days, B finishes the remaining work alone in 44 days. In how many days shall B finish the whole work alone?
Solution:
Let A’s 1 day’s work and B’s 1 day’s work be x and y respectively.
x+ y = 1/30 ----- Equation 1
16x+ 44y = 1 ------ Equation 2
By solving equations 1 and 2, we get x =1/60 and y = 1/60.
B can finish the whole work in 60 days.
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