Let:
x = Original price
xs = Sale price
1st, express the percentage as a decimal:
20% = 20/100 = 0.2
[tex]\begin{gathered} x\cdot0.2=19.56 \\ x=\frac{19.56}{0.2} \\ x=97.8 \end{gathered}[/tex]Therefore, the sale price will be:
[tex]\begin{gathered} xs=x-19.56 \\ xs=97.8-19.56 \\ xs=78.24 \end{gathered}[/tex]Answer:
$78.24