27/6 can be written as 27 divided by 6 to make it easier for you to understand the answer would be 4.5
8pm to 2am, or 8am to 2pm, either way, Carla would've worked for 6 hours.
6*$13=$78
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Carla would earn $78 if she were to clean for 6 hours.
The answer is 9, you have to add them together which equals 9.