Last week , Donnell practiced the piano 3 hours longer than Marcus . Together, Marcus and Donnell practiced the piano 11 hours . For how many hours did each young man practiced the piano
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Answer:
Marcus practiced for 4 hours and Donnell practiced for 7 hours
Step-by-step explanation:
We can set up this problem as a system of linear functions
We'll use d to represent Donnell and m to represent Marcus
Since Donnell practiced 3 hours more than Marcus, we can represent this as an equation:
d=m+3
And since they both practiced for a combined total of 11 hours, we can represent this an an equation:
d+m=11
We can substitute d=m+3 into d+m=11 and we get:
m+3+m=11
2m+3=11
2m=8
m=4
Now we can substitute m=4 into d+m=11
d+4=11
d=7
Therefore, Donnell practiced for 7 hours and Marcus practiced for 4 hours