Write an equation that will relate the number of miles driven to the number of gallons of gas.

Here is the solution ...

This is a proportional relationship.

A proportional relationship is nothing the two quantities vary directly with each other.

The proportional equation y = k x. where k is the constant proportionality.

This means that as x increases, y increases and as x decreases, y decreases.

Here we use the proportional relationship to find the equation.

The number of miles driven is proportional to the number of gallons of gas.

Therefore, the equation is Miles = k Gallons

That is M = k G, where k represents the number of miles driven per gallon of gas.