Question

Jennifer picked up these two videogames for a bargain. Normally,each costs $30. But today therewere 30% off. If she also paid8.25% sales tax, what was the totalbill?

Answer 1

Step 1

Write an expression for the sales tax she paid and the percentage off

`\begin{gathered} \text{Percentage off =30\%. Therefore, the actual \% left = 100 -30 = 70\%} \\ (100)/(70)=\frac{\cos t\text{ of both video games}}{x} \\ \text{where x = cost of video games after the \% off} \\ \end{gathered}`
`\begin{gathered} \text{For the sales tax} \\ (100)/(8.25)=\frac{\cos t\text{ of two shirts}}{y} \\ \text{where y = amount of sales tax paid} \end{gathered}`

Step 2

Find her total bill after substitution

`\begin{gathered} \text{Amount paid after 30\% off will be} \\ (100)/(70)=(60)/(x) \\ 4200\text{ = 100x} \\ x=\text{ }(4200)/(100) \\ x=42\text{ dollars} \end{gathered}`
`\begin{gathered} \text{Amount of sales tax} \\ (100)/(8.25)=(60)/(y) \\ 495\text{ = 100y} \\ y\text{ =\$4.95} \end{gathered}`

Her total bill thereore = 42 +4.95 =$46.95