Please help with a physics: If the energy bar was his only fuel, how far could a 68 kg person walk at 5 km/hr?

An “energy bar” contains 19g of carbohydrates.

According to the website below, 1 gram of carbohydrates supplies 4 kilojoules energy.
http://en.wikipedia.org/wiki/Food_energy

Total energy = 19 * 4 = 76 kJ = 76,000 J

Let’s convert the velocity to m/s. 1 km = 1000 m, 1 hr = 3600 s, 1 km/hr = 1000/3600 = 5/18 m/s
v = 5 * 5/18 = 25/18 m/s
KE = ½ * 68 * (25/18)^2 = 65.28641975 J

I am not sure of how to use these two numbers to determine the distance. Maybe dividing would determine the distance.

76,000 ÷ 65.28641975 = 1158.776471 meters

If energy bar contains 27g, answer is 1700

correct answer

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