A 150lb person who runs at 8 mph for 1 hr burns about 720 ca

A 150lb person who runs at 8 mph for 1 hr burns about 720 calories. The same person, walking at 2mph for 90 min, burns about 120 calories. Suppose a 150-lb person runs at 8mph for 75 min. How far would the person have to walk at 2mph in order to burn the same number of calories as burned when running?

Solution

150-lb person#1 who runs at 8 mph for 1 hr burns about 720 calories.
#miles that 150-lb person runs = 8 miles/hr X 1 hr = 8 mile

same person#1, walking at 2 mph for 90 min (is 1.5hr), burns about 120 calories.
#miles that 150-lb person runs = 2 miles/hr X 1.5 hr = 3 miles

To burn 720 calories walking (same number of calories burned running), that person would need to walk:
720 calories / 120 calories = (x miles) / (3 miles)
x = (720/120)(3 miles)
= (6)(3 miles)
= 18 miles **

To burn the same calaries, the ratio for the (#miles needed to walking**)/(#miles needed to run*) = (18 miles running / 6 miles walking) = 3

Suppose a 150-lb person runs at 8 mph for 75 min (is 1.25hr)
#miles that 150-lb person runs = 8 miles/hr X 1.25 hr = 10 miles

To find out the #miles needed to walk
= (#miles that 150-lb person runs) X (ratio of (#miles needed to walking)/(#miles needed to run))
= (10miles)X(3)
= 30 miles