Identify the constant of Proportionality Write an equation to relate weight, w, to the price, p.

m = .45

p = .45w

.45 = 9/20

Explanation:

m is the rate of change equal to the price over the weight or p/w.

Because this relationship is proportional, each weight divided by its corresponding price must equal the same fraction because it is constant.

We can prove this by dividing each price by its weight to find this proportion.

1.35/3 = 2.7/6 = 27/60 = 9/20 = 0.45

1.71/3.8 = 171/380 = 9/20 = 0.45

2.34/5.2 = 234/520 = 117/260 = 9/20 = 0.45.

Since equal the same value, this means that 9/20 or .45 is our proportion.

in terms of p = mw

p/w = 9/20.

p = mw → p/w = m → m = p/w = .45 .

Thus, p = .45w,

so m = .45.

Which means that for every .45 or 9/20 w or weight, there is a price of $1.