Answer:
7h +11r = 350
Step-by-step explanation:
Let h and r represent minutes of hiking and running, respectively. Then calories burned by a 150-lb person doing these activities will total 350 when ...
7h +11r = 350
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7 calories per minute are burned by hiking, so 7h will be the calories burned by hiking h minutes.
11 calories per minute are burned by running, so 11r will be the calories burned by running r minutes.
The total of calories burned in these activities will be 7h+11r, and we want that total to be 350.