Answers

2014-11-16T14:00:53+05:30
If 
18 men -= 35 days
then
a men = 15 days

so 
x - 18 men - a men
y -  35 days - 15 days
 
i.e. 18x35 = 15 a
then
a = 42
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wrong answer
its wrong dude..
do you think that 7.71 can be mens
see it again
2014-11-16T14:40:49+05:30
Given = 18 men can reap a field in 35 days.
It takes 18×35=630 man-days

1 man can finish work in 630 days
2 men can finish work in 315 days
3 men can finish work in 210 days
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Similarly 
For  how many men are required  for reaping the same field in 15 days.
18 × 35 = 15
18 × 35/15 = 42.

Hence 42 mens can finish same work in 15 days. 

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