Problema Solution

3 people requires 20 days to do a job. How long would it take 4 people to do the same job at the same rate.

Answer provided by our tutors

The rate of the 3 people is : 1/20 (job/days). This means that 1 person can do:

(1/20)(1/3)(job/days)= (1/60) (job/day)


Therefore, 4 people can do:

(1/60)(4)(job/day)=(1/15) job/day


Therefore, it would take 4 people 15 days to do the same job at the same rate.


The rate of the 3 people is : 1/20 (job/days). This means that 1 person can do:

(1/20)(1/3)(job/days)= (1/60) (job/day)


Therefore, 4 people can do:

(1/60)(4)(job/day)=(1/15) job/day


Therefore, it would take 4 people 15 days to do the same job at the same rate.