SEARCH HOME
 Math Central Quandaries & Queries
 Question from taha, a student: A shopkeeper sold a pen for $13.20 to a make a profit 10 percent. In order to earn a profit of 15 percent, he should have sold it for? Taha, Suppose the shopkeeper's cost for a pen is$C. To calculate the profit at 10% he multiplied $C by 0.10 to find the profit and then added it to$C to arrive at $13.20. So his calculation was$C + 0.10 × $C = 1.10 ×$C = $13.20. Solve this equation for$C and then recalculate the selling price, this time using 15% rather than 10%.

I hope this helps,
Penny

Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.