Question

Anna burned 15 calories per minute running for x minutes and 10 calories per minute hiking for y minutes. She spent a total of 60 minutes running and hiking and burned 700 calories. The system of equations shown below can be used to determine how much time Anna spent of each exercise.

15x + 10y =700
x + y = 60

What is the value of x, the minutes Anna spent running?

a) 20

b) 40

c) 10

d) 30

Answer 1

the answer is a 20. 

you do 20 * 15 = 300

700-300 = 400 divide by 10 which is 40 

20(x) + 40(y) equals 60