If the product cost $100 and it has a discount of 18%. The final price is
[tex]100(1-\frac{18}{100})=100(1-0.18)=100(0.82)=82[/tex]that is, It will cost $82.
If the product is mark up 18%, this means that
[tex]\begin{gathered} \text{new price= original price +markup} \\ \text{new price=82+82(18\%)} \\ \text{new price=82}+82(0.18) \\ \text{new price=82+14.76} \\ \text{new price=}96.76 \end{gathered}[/tex]That is, the resulting price is $96.76, which is not equal to $100.
