Question

50 daily workers can complete a dam project in 40 days. If 30 of them work daily and the rest work in every alternative day, how many more days will be required to complete the project.

Answer 1

Total work= 50*40= 2000

In 40 days, daily workers complete: 30*40=1200
Alternate workers complete:20 * (40/2) = 400

Let us assume that they work for x days after 40 days.
Alternate workers will work for x/2 days.

A/Q, 2000 = 1200 + 400 + 30x + 20*(x/2)
Solving, we get x=10

Ans: 10 days

Another Approach:


Total Works: 50*40=2000
30*40=1200
20*20=400
Total =1600


1600….4/5…… 40 days
Total Works: 50*40=2000
30*40=1200
20*20=400
Total =1600

2000………. 1 work
1600…………1600/2000 work or 4/5 work
remain, 1- 4/5=1/5 work

1600….4/5…… 40 days
1600…..1……….(40*5)/4=50
1600…..1/5……..50/5 =10 days