The price of a gallon of unleaded gas was $2.85 yesterday. Today, the price rose to $2.92 . Find the percentage increase. Round your answer to the nearest tenth of a percent.

Accepted Solution

so, the price was 2.85, it went up to 2.92, or $0.07 or 7 cents.

now, if we take 2.85 to be the 100%, what is 0.07 off of it in percentage?

[tex]\bf \begin{array}{ccll} amount&\%\\ \text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\ 2.85&100\\ 0.07&p \end{array}\implies \cfrac{2.85}{0.07}=\cfrac{100}{p}\implies p=\cfrac{0.07\cdot 100}{2.85}[/tex]