Question

Seven-eighths of a work is done by 28 men in a week and then leave it. How many men must be engaged to finish the work in another week.

Answer 1

⅞ of total work done in 7 days by 28 men
therefore 8/8 of work done in 8 days by 28 men
as no. of men inversely proportional to no. of days required
therefore
28 inversely proportional to 8
so 28 = k/8
k = 28*8 = 224
if remaining work must be done in 7 days therefore no. of men = k/7
n = 224/7
n = 32 ---> 32 men can complete the whole job in 7 days
32*⅛ men can complete ⅛ of the job in 7 days
therefore 4 men required to finish the job in a week