A man, a woman and a boy can complete a work in 3,4, and 12 days respectively. How many boys must assist 1 man and 1 woman to complete the job in 1/4 of a day?

Question

Question based on Time and work 

Answer 1

^{man does 1/3 in one day, so 1/12 in a quarter of a day. Woman does 1/4 work in one day, 1/16 in the same time. 1 kid does 1/12 in one day, so 1/48 work in a quarter of a day. Make the common denominator 48, and you equation looks like;}

4/48 + 3/48 +(1/48)x = 1/4 = 12/48

Simplified; 7/48 + (1/48)x = 12/48 or

X/48 = 5/48

X=5, or 5 kids