The school store has a 65% markup on each stapler. Each stapler costs the store $2.10. Find the
Markup amount.

Take the cost of $2.10 times the percentage of the markup of 65% to get your answer. The selling price will be the cost plus the markup.

First, convert your percent into decimal (65% = 0.65). Then multiply your cost (2.10) with your decimal (0.65). That is the 65% mark-up amount.