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 a new man joined the work. The group continued working together till the end of the work. In how many days will they be able to do the remaining work?
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 a new man joined the work. The group continued working together till the end of the work. In how many days will they be able to do the remaining work? Correct Answer 14
Given:
Time taken by 5 men to complete a work = 20 days
Time taken by 10 women to complete a work = 15 days
Formula used:
Work = Efficiency × Time
Calculation:
Five men can complete a work in 20 days = (20 × 5) = 100
Ten women can complete the same work = (15 × 10) = 150
LCM of 100 and 150 is 300
Efficiency of 1 man = (300/100) = 3 units/day
Efficiency of 1 woman = (300/150) = 2 units/day
2 men and 6 women worked together for five days
⇒ (2 × 3 + 6 × 2) × 5
⇒ (6 + 12) × 5
⇒ (18 × 5) = 90 days
Remaining work = (300 – 90) = 210 units
Now,
After 5 days, 3 women left the work = (6women – 3women) = 3women
And 1 man joined the work = (1man + 2man) = 3man
Time taken to complete the remaining work by 3 women and 3 men is
⇒
⇒
⇒
⇒ (210/15) days
⇒ 14 days
∴ The required time is 14 days
Shortcut TrickHere we need to equal number of men and women,
Ten women can complete the work in 15 days
So, five women can complete the work in 30 days
Now,
2 men and 6 women together = (2 × 3 + 6 × 2) × 5 = 90 units in five days
Remaining = 300 - 90 = 210 units
Now,
Time taken by 3 men and 3 women to complete the remaining work = = 14 days