38.0k views
9 votes
a worker can do a job in 5 hrs and his student can do the same job in 8 hrs. What part of the job is left if they start the job and work together for 2 hrs. What part of the work is left to finish?(picture if you do not understand)

a worker can do a job in 5 hrs and his student can do the same job in 8 hrs. What-example-1

1 Answer

3 votes

Answer:

7/20

Explanation:

Let's do this.

The worker can work 1/5 job in an hour and the student can do 1/8 job in an hour. 1/5 + 1/8 = 13/40. The worker and the student together can do 13/40 job in an hour. If we multiply 13/40 by 2, we get 13/20 and that is 2 hours.

So 20/20 - 13/20 = 7/20.

They have 7/20 of the job left to finish.

User Alexey Palamar
by
8.2k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories