550 peoples can complete a work in 100 days. After 10 days start of the work 50 more people join. In how many more days now the work will be completed?
Answers
550 people can do the work in 100 days
⇒ 1 day = 1/100 of the work
Find the amount of work completed by 550 people in 10 days:
1 day = 1/100
10days = 1/100 x 10 = 10/100 = 1/10 of the work
Amount of work left to do after the 10 days:
Amount of work left = 1 - 1/10 = 9/10 of the work
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Number of people after 50 joined in:
550 + 50 = 600 people
Find the number of days needed for 600 people to complete the work:
550 people = 100 days
1 person = 100 x 550 = 55000 days
600 people = 55000 ÷ 600 = 275/3 days
Find the number of days needed to complete the rest of the work:
Rest of the work = 9/10 of the work
whole work = 275/3 days
9/10 of the work = 9/10 x 275/3 = 82.5 days
Answer: They need another 82.5 days