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3 years ago

Rhonda worked three more than twice as many hours as Chris did. How many hours did each work if together they worked 57 hours

Mathematics

1 answer:

Elan Coil [88]3 years ago

4 0

Answer:

Rhonda: 39 hours; Chris: 18 hours.

Step-by-step explanation:

If you subtract the extra 3 hours from the total, you have Chris's hours plus twice Chris's hours adding to 54. That is, Chris worked 54/3 = 18 hours, and Rhonda worked 57-18 = 39 hours = 2·18 +3 hours.

_____

If you insist on equations, you can write two of them:

... r = 2c +3

... r + c = 57

Substitute for r in the second equation:

... (2c +3) +c = 57

... 3c +3 = 57 . . . . . from here down, the explanation above matches this math

... 3c = 54

... c = 54/3 = 18

... r + 18 = 57 . . . . . . substitute for c in the second equation

... r = 57 - 18 = 39

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