A merchant has selected two items to be placed on sale, one of which currently sells for 45 percent less than the other. If he wishes to raise the price of the cheaper item so that the two items are equally priced, by what percentage must he raise the price of the less expensive item?  Options
A) 100 %  B) 90 %  C) 80 %  D) 70 %  E) 60 %

Rationale: "expensive item = $ 100 ; cheap item = $ 55 ; we must increase $ 55 to $ 100 , so by $ 45 , which is approximately 80 % increase : ( 100 - 55 ) / 55 = 3 / 7 = ~ 0.81 . answer : c ."
Answer: C