Question

Martin burns 360 calories running for 30 minutes. Paul burns 165 calories for every 15 minutes he runs. If Kara runs for 20 minutes, how many calories would she have to bum to have a rate of calories burned per minute of running that is between Martin and Paul?

Answer 1

step 1

Find out the rate of calories of Martin

divide the total calories by the total time

so

360/30=12 calories/min

step 2

Find out the rate of calories of Paul

165/15=11 calories/min

step 3

Find out the rate of calories of Kara

we know that

the rate of calories of Kara is between Martin and Paul

so

I will assume that is the midpoint between 11 and 12

so

11.5 calories/min

Let

x -----> the number of calories

we have

11.5=x/