1 pineapple and 1 pear can be exchanged for 7 bananas, 3 pears can be exchanged for 6 bananas, and 1 pineapple can be exchanged for how many bananas.
1个菠萝和1个梨能换7个香蕉，3个梨能换6个香蕉，1个菠萝可以换多少个香蕉．
<gadget id="calculator">6 / 3</gadget>
<output>2</output>

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

<result>5</result>