SOLUTION: an athlete can burn 12 calories per minute while running and 5 calories per minute while walking. if the athlete burns 580 calories in 60 minutes, how long is spent on each activit

Algebra ->  Test -> SOLUTION: an athlete can burn 12 calories per minute while running and 5 calories per minute while walking. if the athlete burns 580 calories in 60 minutes, how long is spent on each activit      Log On


   

Question 1141265: an athlete can burn 12 calories per minute while running and 5 calories per minute while walking. if the athlete burns 580 calories in 60 minutes, how long is spent on each activity?
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Typical Constant Rates problem with two separate uncombined tasks. 

           RATE           TIME           CALORIES

RUN          12

WALK          5

Totals                      60              580



           RATE           TIME           CALORIES

RUN          12            r              12r

WALK          5            w               5w

Totals                     60             580

12r%2B5w=580
r%2Bw=60
-
12r%2B5%2860-r%29=580
12r%2B300-5r=580
7r=580-300
7r=280
highlight%28r=40%29------------time in minutes spent running.