The total amount she would make next week if she worked for 15 hours is $256.50.
The first step is to determine how mcuh Grace earns per hour. This can be determined by dividing the amount earned by 8 hours
Hourly wage = $136.80 /8 = $17.10
Now, multiply the hourly wage by the number of hours worked: 15 x 17.10 = $256.50
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