If 7 men and 9 women can do a piece of work in 13 days and 5 men and 7 women can do it in 17 days, h

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23 May 2018 Work & Time

If 7 men and 9 women can do a piece of work in 13 days and 5 men and 7 women can do it in 17 days, how

many days will 6 men and 11 women take to do half of it?

OPtion

1) 13.66
2) 10.50
3) 11.33
4) 12.33
5) 12.5
6) 5.33
7) 6.66
8) 11.00
9) 13.33
10) None of these

Solution

Let a man's daily work is x units and that of a woman is y units.
So total amount of work, W = 13(7x + 9y) = 17(5x + 7y)

Solving we get, 91x - 85x = 119y - 117y
=> 6x = 2y
=> y = 3x


Now, 7 x + 9 y can do work in 13 days.
So, 7x + 27x can do work in 13 days.
So, 34 x can do work in 13 days.

Now, 6x + 11y = 6x + 33x = 39x

Hence, if 34 x can do work in 13 days, 39x can do work in (13*34)/39 = 11.33 days.

Time taken to do half of the work= 11.33/2 = 5.665

Option 10)

Correct Option: 10 Best Solution (0)