Algebra
posted by Rachal .
Miguel is choosing between two exercise routines.
In Routine #1, he does only running, burning 15 calories per minute.
In Routine #2, he burns 12 calories walking. He then runs at a rate that burns 12 calories per minute.
For what amounts of time spent running will Routine #1 burn more calories than Routine #2? Use t for the number of minutes spent running, and solve your inequality for t.

It would help if you proofread your questions before you posted them.
From your data, all I get is:
15t > 12t, which applies for all values of t. 
During 30 minutes on the treadmill, Latoya burned 20 calories per minute. What is the rate of change of the function that represents this situation?

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