8 pears can be exchanged for 2 pineapple, 10 pineapple can be exchanged for 2 watermelons, how many pears can be exchanged for 3 watermelons?
8个梨换2个波萝，10个波萝换2个西瓜，3个西瓜能换多少个梨．
<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">8 * 5</gadget>
<output>40</output>

<gadget id="calculator">40 / 2</gadget>
<output>20</output>

<gadget id="calculator">20 * 3</gadget>
<output>60</output>

<result>60</result>