Five men can complete a work in 20 days. Ten women can complete the same work in 15 days. Two men and six women started working together. After 5 days, three women left the work and a new man joined the work. The group continued working together till the end of the work. In how many days they be able to do the remaining work?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 14
Let the efficiency of 1 man = 'm' units and efficiency of 1 woman = 'w' units
5m × 20 = 10w × 15
m/w = 3/2.
The efficiency of 1 man = 3 units/day and the efficiency of 1 woman = 2 units.
Total work = 5 × 3 × 20 = 300 units.
2 men and 6 women start working,
They completes 2 × 3 + 6 × 2 = 18 units of work daily.
In 5 days, 90 units of work comoleted.
Now 3 women left and 1 new men joined the group.
They complete 3 × 3 + 3 × 2 = 15 units of work each day.
Remaining work = 300 - 90 = 210 units.
Time taken by them to finish the work = 210/15 = 14 days.