94.2k views
1 vote
It takes a new mail carrier 4 hours to deliver the mail on route a. It takes an experienced mail carrier 3 hours to do the same job. How long would it take if they worked together?

1 Answer

5 votes

Answer:
(12)/(7)\ \text{hours}

Explanation:

Given

New mail carrier takes 4 hours for delivery i.e.

New mail carrier completes
(1)/(4) part of work in 1 hour

Old mail carrier takes 3 hours for delivery i.e.

mail carrier completes
(1)/(3) part of work in 1 hour

If they work together, they complete the work in x hours i.e.


\Rightarrow (1)/(x)=(1)/(4)+(1)/(3)\\\Rightarrow (1)/(x)=(3+4)/(12)\\\Rightarrow x=(12)/(7)\ \text{hours}

User Alex Grin
by
8.1k 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