There are 10 people in a group, 7 people like to eat bananas, 5 people like to eat apples, how many people like to eat both bananas and apples?
一个小组有10个人，7个人爱吃香蕉，5个人爱吃苹果，问既爱吃香蕉又爱吃苹果的有几个人？
<gadget id="calculator">5 - 10</gadget>
<output>-5</output>

<gadget id="calculator">7 + (-5)</gadget>
<output>2</output>

<result>2</result>