A man, a woman and a boy can complete a work in 3, 4 and 12 days, respectively. How many boys must assist one man and one woman to complete the same work in one day?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 5
Formula used:
Total work = Efficiency × time
Calculations:
Let the total work be 12 units (LCM of 3, 4 and 12)
Efficiency of man = 12/3 = 4 units
Efficiency of woman = 12/4 = 3 units
Efficiency of boy = 12/12 = 1 unit
Total efficiency should be 12 units per day to complete the work in one day
Efficiency of one man and one woman = 4 + 3 = 7 units
Remaining work = 12 - 7 = 5 units
Efficiency of boy = 1 units
So total boys required = 5 × 1 = 5