180
60
25
20
Correct answer is D
Let x represents number of boys that can work at 54 the rate at which the 10 girls work
For 1hr. x boys will work for 154 x 10
x = 45 x 10 = 8 boys
8 boys will do the work of ten girls at the same rate 4 + 8 = 12 boys cut the field in 5 hrs
For 3 hrs, 12×53 boys will be needed = 20 boys
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