The school bought 4 desks and 9 chairs for 504 yuan. Given that a chair is 48 yuan cheaper than a table, how much does a set of chairs cost?
学校买了4张课桌和9把椅子共用去504元．已知一把椅子比一张桌子便宜48元，一套课椅要多少元？
<gadget id="calculator">4 * 48</gadget>
<output>192</output>

<gadget id="calculator">504 - 192</gadget>
<output>312</output>

<gadget id="calculator">9 + 4</gadget>
<output>13</output>

<gadget id="calculator">312 / 13</gadget>
<output>24</output>

<gadget id="calculator">72 + 24</gadget>
<output>96</output>

<result>96</result>