Chapter B.1, Problem 23E

To determine

the percentage rate of decrease in price from 2012 to 2016.

Answer to Problem 23E

The percentage decrease in price from 2012 to 2016 is $37.83\%$ .

Explanation of Solution

Given information:

The given line graph of the average price of gasoline is

  

Formula used:

Formula of percentage decrease:

  $\%decrease=\frac{initialvalue-finalvalue}{initialvalue}\times 100$

Note the average price of gasoline in the year 2012 and 2016 from the above graph.

  $2012=\$3.70/\text{gallon}$

  $2016=\$2.30/\text{gallon}$

Calculate the percentage decrease using the formula:

  $\%decrease=\frac{initialvalue-newvalue}{initialvalue}\times 100$

Substitute $\$3.70/\text{gallon}$ for initial value and $\$2.30/\text{gallon}$ for final value in the above expression.

  $\begin{array}{c}\%decrease=\frac{3.70-2.30}{3.70}\times 100\\ =37.83\%\end{array}$

Hence, the percentage decrease in price from 2012 to 2016 is $37.83\%$ .