The cost, c,

of paper towels, based on the number of rolls, r,
is given by this equation.

c=1.29r

What is the unit rate of the cost of the paper towels in dollars per roll?

Enter your answer as a decimal, like this: 42.53

1 answer

To find the unit rate of the cost of the paper towels in dollars per roll, you need to divide the total cost by the number of rolls.

Given the equation: \[ c = 1.29r \]

The unit rate can be found by isolating the cost per roll, which is expressed as: \[ \text{Cost per roll} = \frac{c}{r} \]

Substituting the equation for cost: \[ \text{Cost per roll} = \frac{1.29r}{r} \]

When you simplify that, the \( r \) cancels out: \[ \text{Cost per roll} = 1.29 \]

Thus, the unit rate of the cost of the paper towels is \( 1.29 \) dollars per roll.

So the answer is: \[ 1.29 \]