a. sale 15% off
he paid $150
We have:
100% - 15% = 85%
We can express 85% as 0.85 this is what was paid for the coat. Then
let x = original price
[tex]\begin{gathered} 150=x\cdot0.85 \\ \frac{150}{0.85}=x\cdot\frac{0.85}{0.85} \\ x=176.47 \end{gathered}[/tex]Answer: the original price was $176.47
b. We have:
change by -23%
the account's value $26,160
let x = value before this change
[tex]\begin{gathered} 26160=x-x\cdot0.23 \\ 26160=x(1-0.23) \\ 26160=x\cdot0.77 \\ \frac{26160}{0.77}=x\cdot\frac{0.77}{0.77} \\ x=33974.03 \end{gathered}[/tex]Answer: the value before this change was $33,974.03
