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5 votes
Working together, Melissa and Jing can mow a lawn in 5 hours. It would take Melissa 8 hours to do the job alone.

What is the value of r, the part of the lawn that Jing could complete in 1 hour?

0.075
0.125
0.375
0.625

User Miko Chu
by
5.5k points

2 Answers

6 votes

Answer:

a. 0.075

Step-by-step explanation: just took the test

User Medk
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5 votes
The part Jing can complete in an hour is the rate or speed per hour that Jing can mow.

rate = 1/time, So Melissa's rate = 1/8

The combined rate = 1/5

The combined rate is found simply by adding the two individual rates.

1/8 + J = 1/5

J = 1/5 - 1/8

J = .075
User Cruz
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6.0k points