SOLUTION: Michael and John work together building houses. Michael's crew can build a house in 8 days, while John's crew can finish the same house in 10 days. How long would it take both crew

Question 1070207: Michael and John work together building houses. Michael's crew can build a house in 8 days, while John's crew can finish the same house in 10 days. How long would it take both crews if the worked together?
Found 2 solutions by jorel1380, ikleyn:
Answer by jorel1380(3719)   (Show Source): You can put this solution on YOUR website!
If Michael's crew can build a house in 8 days, then they finish 1/8th of a house per day. Similarly, John's crew finishes 1/10th of a house per day. Working together, they can finish:
1/8 + 1/10=5/40 + 4/40, or 9/40ths of a house per day. Therefore, 1 house takes 1/(9/40), or 40/9, or 4-4/9ths days. ☺☺☺☺
Answer by ikleyn(52756)   (Show Source): You can put this solution on YOUR website!
.
Michael and John work together building houses. Michael's crew can build a house in 8 days, while John's crew can finish
the same house in 10 days. How long would it take both crews if the worked together?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Michael's crew makes of the job per day. John's crew makes of the job per day. When the two crews work together, they make = = of the work per day. Hence, it will take = days for the two crews to complete the job.

It is very typical joint-work problem.

For a wide variety of similar solved joint-work problems with detailed explanations see the lessons
    - Using Fractions to solve word problems on joint work,
    - Solving more complicated word problems on joint work,
    - Selected joint-work word problems from the archive
in this site.

Read them and get be trained in solving joint-work problems.

Also, you have this free of charge online textbook in ALGEBRA-I in this site
    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this textbook under the topic "Rate of work and joint work problems" of the section "Word problems".

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