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 \\ (0.42)/(3.49)=x \\ x=0.12 \end{gathered}`

and the percentage is

`\begin{gathered} 0.12*100 \\ =12 \end{gathered}`

12%