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WE:Education (Education)
If 6 men and 4 boys can reap 24 acres in 3 days,
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19 Feb 2021, 02:11
OA Explanation
When we have a comparison between Men, Time and Work, Use:
M1 x T1 x W2 = M2 x T2 x W1
Here,
M1 = (6M + 4B)
T1 = 3
W1 = 24
M2 = (2M + 3B)
T2 = 6
W2 = 18
M3 = (8M + xB)
T3 = 4
W3 = 44
So,
\(\frac{(6M + 4B)(3)}{24} = \frac{(2M + 3B)(6)}{18}\)
\(18M + 12B = 16M + 24B\)
\(2M = 12B\)
\(M = 6B\)
Now, we can equate the third case with any of one of the two;
\(\frac{(2M + 3B)(6)}{18} = \frac{(8M + xB)(4)}{44}\)
\(\frac{(2M + 3B)}{3} = \frac{(8M + xB)}{11}\)
Plug \(M = 6B\) in the above equation:
\(\frac{(12B + 3B)}{3} = \frac{(48B + xB)}{11}\)
\(\frac{15B}{3} = \frac{(48 + x)B}{11}\)
\(5 = \frac{(48 + x)}{11}\)
\(55 = (48 + x)\)
\(55 - 48 = x\)
\(x = 7\)
Hence, 7 boys must assist those 8 men