Given data: Rate of computer is 21,000 and the marigin is 30%
selling price = original price +profit margin.
Thus, the selling price is $27300.
[tex]\begin{gathered} \text{Profit marigin =}\frac{30}{100}\cdot21000=6300. \\ So,\text{ selling price= 21000+6300=}27300 \end{gathered}[/tex]