Since the final price Kevin paid is $63, we need to "remove" the tax rate and the discount.
To do so, we can divide by 1.05 (+5%) to remove the tax rate and by 0.8 (-20%) to remove the discount.
So we have:
[tex]\text{Price}=\frac{63}{1.05\cdot0.8}=\frac{63}{0.84}=75[/tex]So the original price is $75
