.
Their combined rate of work is of the manuscript per hour.
Subtract of the manuscript per hour, which is Rebecca's rate, from it:
= = ,
and you will get the Jessa rate.
Thus Jessa will type the manuscript in 12 hours working alone.
Answer. Jessa will type the manuscript in 12 hours working alone.
Solved.
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The lesson to learn from this solution:
You can distract from the combined rate to get the individual rate.
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It is typical joint work problem.
There is a wide variety of similar solved joint-work problems with detailed explanations in this site. 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
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".