Question

Last Week: $3.49This Week: $3.07. What is the percent change in the price of a gallon gas, to the nearest whole percent?

Answer 1

we can write an equation

$3.49-3.49x=3.07$

where x is the change

now, solve x

$\begin{gathered} 3.49-3.07=3.49x \\ \frac{0.42}{3.49}=x \\ x=0.12 \end{gathered}$

and the percentage is

$\begin{gathered} 0.12\times100 \\ =12 \end{gathered}$

12%