There are 15 more volleyballs than footballs in the sports room, and 23 footballs and 15 volleyballs were purchased later. Is there more volleyball or football now? How many more?
体育室里的排球比足球多15个，后来又购进了23个足球和15个排球．现在是排球多还是足球多？多多少个？
<gadget id="calculator">23 - 15</gadget>
<output>8</output>

<gadget id="calculator">15 - 8</gadget>
<output>7</output>

<result>7</result>