The school bought 4 desks and 9 chairs for a total of 252 yuan. The price of a chair is exactly (1/3) of a desk. How much is the unit of a desk.
学校买来4张办公桌和9把椅子，共用252元．一把椅子的价钱正好是一张办公桌的(1/3)．一张办公桌的单位是多少元．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">9 * (1/3)</gadget>
<output>3</output>

<gadget id="calculator">4 + 3</gadget>
<output>7</output>

<gadget id="calculator">252 / 7</gadget>
<output>36</output>

<result>36</result>