Xiaolin bought 5 CDs, and Xiaofang bought 3 identical CDs, which cost 20 yuan less than Xiaolin's. How much is a CD?
小林买了5张光盘，小芳买了3张同样的光盘，比小林少花了20元钱，一张光盘多少钱？
<gadget id="calculator">5 - 3</gadget>
<output>2</output>

<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<result>10</result>