A man, a woman and a boy can complete a job in 3 days, 4 days and 12 days respectively. How many boys must assist 1 man and 1 woman to complete the job in 1/4th of a day? Choose the most appropriate option
A) 10 B) 41 C) 31 D) 21 E) 22
Explanation:   1 man’s 1 day’s work = 1/3, ¼ day’s work = 1/3 × ¼ = 1/12   1 woman’s 1 day’s work = ¼, ¼ day’s work = ¼ × ¼ = 1/16   1 boy’s 1 day’s work = 1/12, ¼ day’s work = 1/12 × ¼ = 1/48   Let ‘x’ be the No. of boys required.   Then, (1 man + 1 woman + x boy)’s ¼ day’s work 1/12 + 1/16 + x/48 = 1   = (4 + 3 + x)/48 = 1   i.e. 7 + x= 48 and x = 41.   Answer: Option 41
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A man, a woman and a boy can complete a job in 3 days, 4 days and 12 days respectively. How many boys must assist 1 man and 1 woman to complete the job in 1/4th of a day?