If 12 men and 16 boys can do a piece of work in 5 days; 13 men and 24 boys can do it in 4 days, then the ratio of the daily work done by a man to that of a boy is? Select
A) 2:1 B) 2:8 C) 2:9 D) 2:5 E) 2:2
Let 1 man's 1 day work = x and 1 boy's 1 day work = y.   Then, 12x + 16y = 1/5 and 13x + 24y = 1/4   Solving these two equations, we get:   x = 1/100 and y = 1/200   Required ratio = x:y = 1/100 : 1/200 = 2:1.   2:1nswer: 2:1
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If 12 men and 16 boys can do a piece of work in 5 days; 13 men and 24 boys can do it in 4 days, then the ratio of the daily work done by a man to that of a boy is?