A coat is priced at 135 yuan after a 25% discount, how much cheaper than the original price?
一件上衣打七五折后售价135元，比原价便宜多少元？
<gadget id="calculator">75 / 100</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">135 / (3/4)</gadget>
<output>180</output>

<gadget id="calculator">180 - 135</gadget>
<output>45</output>

<result>45</result>