A kind of umbrella is on sale at an "85" discount, and my mother bought one for 8.5 yuan. How much is the original price of this umbrella?
一种雨伞打"八五"折出售，妈妈用8.5元买得一把，这种雨伞原价多少元？
<gadget id="calculator">85 / 100</gadget>
<output>17/20 = around 0.85</output>

<gadget id="calculator">8.5 / (17/20)</gadget>
<output>10</output>

<result>10</result>