Question

if I take 10 people 20 days complete the internal of the building how many days will it take for 5 people to complete the same job

Answer 1

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Total work in units = 40 units ( i.e the LCM of 20,10 and 8)

Rate of work done by 10 people = total work / time taken

Rate of work by 10 people = 40units / 20 days = 2units/day

Rate of work by 1 person = 2 /10 = 1/5

Rate of work by 8 person = 8 × 1/5 = 8/5

Time taken by 8 person = total work / rate of work by 8 person

= 40 units / (8/5) units/day

25 days