A young sumo wrestler decided to go on a special diet to gain weight rapidly. He gained weight at a constar

rate.

The table compares the wrestler's weight (in kilograms) and the time since he started his diet (in months).

Time (months) Weight (kilograms)

0.5

80.6

88.4

2

3.5

96.2

How fast did the wrestler gain weight?

kilograms per month

5.2 kg per month.

Explanation:

The measure of how fast the wrestler gained weight, in kg per month, is the weight gain rate.

The table is:

Time (months) Weight (kg)

0.5 80.6

2 88.4

3.5 96.2

The weight gain rate, WGR, for a period may be calculated as:

WGR = [ weight gain ] / [period]

WGR = [final weight - initial weight] / [final time - initial time]

WGR₁ = [88.4 kg - 80.6 kg] / [2 month - 0.5 month] = 7.8 kg / 1.5 month = 5.2 kg / month

WGR₂ = [96.2 kg - 88.4 kg] / [3.5 month - 2 month] = 7.8 kg / 1.5 month = 5.2 kg / month.

As you see, the wrestler gained weight at a constant rate of 5.2 kg per month.