The school bought 12 sets of single-person desks and chairs, one desk was 75 yuan, and one chair was 55 yuan. How much more did it cost to buy a table than a chair?
学校买来12套单人课桌椅，一张桌子75元，一把椅子55元，买桌子比椅子多用了多少元？
<gadget id="calculator">75 - 55</gadget>
<output>20</output>

<gadget id="calculator">20 * 12</gadget>
<output>240</output>

<result>240</result>