A contractor employed 210 men to built a house in 60 days. After 12 days, he was joined by 70 more men.In how many days will the remaining work will be finished?
Answers
If you multiply 210 by 60 then you figure out how many days it would take one person to do the whole project by himself (12600 days).
Then you multiply 210 by 12 to see how many of those days the 210 workers have already completed in the 12 days (2520)
Next subtract 2520 from 12600 to see how many days a single person would have left (10080)
Then you would add the 70 new people to the original 210 (280)
Divide the days left (10080) by the people (280) to get your
answer- 36.
210 men can build the house in 60 days
⇒ 1 day = 1/60 of the house
Find amount of work left after 12 days:
1 day = 1/60
12 days = 1/60 x 12 = 12/60 = 1/5
Work left to do = 1 - 1/5 = 4/5
Number of men after 70 more joined in:
Total men = 210 + 70 = 280
Find the the number of days needed for the 210 men to complete the work:
210 men = 60 days (Given)
1 man = 60 x 210 = 12600 days
280 men = 12600 ÷ 280 = 45 days
280 me can build the house in 45 days
⇒ 1 day = 1/45 of the house
Find the number of days 280 men will need to complete the work:
Number of days = 4/5 ÷ 1/45 = 36 days
Answer: The remaining work will be finished in 36 days