On a purchase of $110, a store offered a payment plan consisting of a $10 down payment and 12 monthly payments of $10 each. What percent of the purchase price, to the nearest tenth of a percent, did the customer pay in interest by using this plan? Options.
A) 9.5%
B) 10.5%
C) 11.5%
D) 9.1%
E) 12.5%
12*10 + 10= 
<gadget id="calculator">12*10 + 10</gadget>
<output>130</output>
130   (10/110)* 100= 9.1   Answer : 9.1%
<result>D</result>
On a purchase of $110, a store offered a payment plan consisting of a $10 down payment and 12 monthly payments of $10 each. What percent of the purchase price, to the nearest tenth of a percent, did the customer pay in interest by using this plan?