Time & Work
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- sumgb
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Let's call rate of 1 Man = Rm and
rate of 1 Woman = Rw
We know, Rate * Time = Work
Here, 3Rm (43) = 1 and 4Rw (43) = 1 So,
Rm = 1 / (3 * 43) and Rw = 1 / (4 * 43)
Combined rate of 7 Men = 7 / (3 * 43)
Combined rate of 5 Women = 5 / (3 * 43)
So combined rate of 7 men and 5 women, Rc = 7 / (3 * 43) + 5 / (3 * 43)
which is 1 / 12
so, since RT = W; (1 / 12) * T = 1 so time taken by 7men and 5women = 12 Days.
Hope this helps...
rate of 1 Woman = Rw
We know, Rate * Time = Work
Here, 3Rm (43) = 1 and 4Rw (43) = 1 So,
Rm = 1 / (3 * 43) and Rw = 1 / (4 * 43)
Combined rate of 7 Men = 7 / (3 * 43)
Combined rate of 5 Women = 5 / (3 * 43)
So combined rate of 7 men and 5 women, Rc = 7 / (3 * 43) + 5 / (3 * 43)
which is 1 / 12
so, since RT = W; (1 / 12) * T = 1 so time taken by 7men and 5women = 12 Days.
Hope this helps...
- Ozlemg
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Very good explanation. there is a little typosumgb wrote:Let's call rate of 1 Man = Rm and
rate of 1 Woman = Rw
We know, Rate * Time = Work
Here, 3Rm (43) = 1 and 4Rw (43) = 1 So,
Rm = 1 / (3 * 43) and Rw = 1 / (4 * 43)
Combined rate of 7 Men = 7 / (3 * 43)
Combined rate of 5 Women = 5 / (4 * 43)
So combined rate of 7 men and 5 women, Rc = 7 / (3 * 43) + 5 / 4 * 43)
which is 1 / 12
so, since RT = W; (1 / 12) * T = 1 so time taken by 7men and 5women = 12 Days.
Hope this helps...
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