A set of sportswear is priced at 850 yuan and is now sold at a 15% discount. How much is this set of sportswear cheaper?
一套运动服标价850元现打八五折出售这套运动服便宜多少元．
<gadget id="calculator">85 / 100</gadget>
<output>17/20 = around 0.85</output>

<gadget id="calculator">1 - (17/20)</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">850 * (3/20)</gadget>
<output>255/2 = around 127.5</output>

<result>255/2 = around 127.5</result>