The original price of a commodity is 60 yuan, and it is sold after a 10% discount. How much is it cheaper?
一种商品原价60元，打九折后出售，便宜了多少元．
<gadget id="calculator">90 / 100</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">1 - (9/10)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">60 * (1/10)</gadget>
<output>6</output>

<result>6</result>