85 table tennis balls are put into 3 boxes and there are 13 left. How many table tennis balls are in each box?
85个乒乓球，装进3只盒子后还剩下13个，每只盒子装乒乓球多少个？
<gadget id="calculator">85 - 13</gadget>
<output>72</output>

<gadget id="calculator">72 / 3</gadget>
<output>24</output>

<result>24</result>