SOLUTION: alice can do a job in 4 hours, christina can do the same job in 5 hours. how long would it take if they work togehter

Question 1055665: alice can do a job in 4 hours, christina can do the same job in 5 hours. how long would it take if they work togehter
Answer by ikleyn(52814) (Show Source): You can put this solution on YOUR website!
.
See the lesson
- Using Fractions to solve word problems on joint work
in this site.

You will find a lot of prototypes/samples there.

Read it attentively and then solve your problem by substituting your data.

In couple lines, the solution is 

 =  =  

is the combined rate of work of A and C working together.
It means that they both can complete the job in    hours.

For details see the lesson above.

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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