if a 160 pound person burns 73 calories in 20 minutes. show linear model on how long it takes to burn 438 calories?
let x = the rate the calories are burned
in this problem the weight of the person is not needed.
rate * time = total calories burned
x * 20 = 73
20x = 73
x = 73/20 = 3.65 calories burned per minute is the rate
apply this rate to 438 calories to find the time needed to burn them.
438/ 3.65 = 120 minutes