Question

A can complete a piece of work on 15 days and B can complete the same work in 12 days. If

both of them work together how long will they take to finish the work?

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Answer 1

This is a work problem where you are trying to find the amount of work that each A and B can do in one day then find out how long it will take for them to do it together. with that, A can do 1/15 of the job in a day, and B can do 1/12 of the job in a day. Together they can do 1/15+1/12 in a day. When you add them together you will get 4/60+5/60=9/60 of the job done in a day. so now the job is to find out how much time it will take for them to do the entire job, so 9/60*x=1 job. Solve for x by multiplying by the reciprocal on each side. (60/9)(9/60x)=1(60/9) which will produce x to be 60/9 or 6 and 2/3 of a day to work together.

the work is shown below

(1/15+1/12)x=1

((1*4/15*4)+(1*5/12*5))x=1

(4/60+5/60)x=1

(9/60)x=1

(60/9)(9/60)x=1(60/9)

x=6 2/3 or 6.6666666 days to do the job together.

Answer 2

Answer:

$x = 6 \frac{2}{3}$