Question

You have 40 minutes to exercise at the gym, and you want to burn 300 calories total using both

machines. The amount of calories burned on each machine is shown in the picture below. How
much time should you spend on each machine?


Machine a burns 8 calories per minute machine b burns 6 calories per minute.

Answer 1

a and b are the minutes spent on machine A and machine B, respectively.

a+b = 40
b = 40-a

8a + 6b = 300
8a + 6(40-a) = 300
8a + 240 - 6a = 300
2a = 60
a = 30
b = 40-a = 10

30 minutes on machine A and 10 minutes on machine B