Problema Solution

An athlete can burn 9 calories per minute on a stationary

Bicycle and 11.5 calories per minute on a stair climber.

In a 30-minute workout an athlete burns 300 calories. How many minutes does the athlete spend on each type of exercise equipment?

Answer provided by our tutors

Let the time spent on the stationary bicycle be x minutes and that spent on stair climber be y minutes. Then according to the question:

 9x + 11.5 y = 300   (1)

And the total time is 30 minute, so 

x+y=30    (2)

Multiplying (2) with 9 we get

9x + 9y = 270   (3)

(1) - (3) gives

2.5y = 30

=> y = 30/2.5 = 12 minutes.

Putting this value of y in (2), we get x = 30-12 = 18 minutes