A work can be finished in a day by 20 men, or by 30 women, or by 50 boys. 2 men and 5 boys work on alternate days and 6 women work on all days. If men work on the first day, the work is finished in ____ days.
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. .
Men’s day: 2 men + 6 women
Rate = 2 × 120 + 6 × 130 = 110 + 15 = 0.1 + 0.2 = 0.3 (i.e. 3/10)
Boys’ day: 5 boys + 6 women
Rate = 5 × 150 + 6 × 130 = 110 + 15 = 0.1 + 0.2 = 0.3 (i.e. 3/10)
Time = Total work/Work per day = 1/0.3 = 10/3 days = days