Markup = original cost × percentage markup selling price = original cost + markup the manufacturing cost of a cell phone was $124. sellers first marked up the cost by 20 percent. sales were poor, so sellers decreased the markup to 15 percent. calculate the old and new selling prices.

a. old price: $170.00; new price: $148.80
b. old price: $142.60; new price: $148.80
c. old price: $148.80; new price: $142.60