Quote:
Originally Posted by RMKamran
Aoa,
Kindly solve this question. In this question, two different people are doing the same work, and this is confusing me in its solution 
If 3 men or 6 boys can do a work in 20 days, then 6 men and 8 boys shall take:
A. 6 days.
B. 8 days.
C. 9 days.
D. 20 days.
P.S: Quick and detailed reply would be highly appreciated. Thanks in anticipation.
Regards. |
Quote:
Originally Posted by Mashaaal
my answer is 7.5 (approx 8 because 8 is not in the options)
the number of men and boys is increasing so they will be doing the work in less days, therefore men and boys are at inverse with days (so it is indirect proportion)
having a test tomorrow?
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3 men = 6 boys
Then, 1 boy = 3/6 men = 1/2 men
8 boys = 1/2 × 8 men = 4 men
Then, 6 men + 8 boys = 6 + 4 men = 10 men
work done = 3 men × 20days
That is, 3 × 20 = 10 × (required days)
3 × 2 = 1 × (required days)
so (required days) =6.