Amusic store bought a cd set at a cost of $10. when the store sold the cd set, the percent markup was 30%. find the selling price. explain thxs hooman

The selling price is $13.

First, you multiply the percent by the original price. 
$10 *.30 = $3

Then, add the above answer to the original price to get the new selling price. 
$10 + $3 = $13