Answer:10 days
Explanation:
75 men could complete a piece of work in 20 days
When work was scheduled to commence, it was found necessary to send 25men to another project. This means that lesser number of men will do same work and it will take them more days. This is an inverse proportion
For inverse proportion, let us introduce constant k
Number of men, n is inversely proportional to number of days, d
n is inversely proportional to d
We introduce k which is our proportionally constant
n =k/d
When n = 75 and d = 20,
k = 20×75 = 1500
So we have
n =1500/d
Since 25 men left, 50 men would be remaining to do the work
50 = 1500/d
d = 1500/50
= 30 days
It will take 50/men 10 days more