2 watermelons can be exchanged for 6 apples, 3 apples can be exchanged for 12 peaches, how many peaches can be exchanged for 1 watermelon?
2个西瓜换6个苹果，3个苹果换12个桃，1个西瓜能换多少个桃．
<gadget id="calculator">6 / 3</gadget>
<output>2</output>

<gadget id="calculator">12 * 2</gadget>
<output>24</output>

<gadget id="calculator">24 / 2</gadget>
<output>12</output>

<result>12</result>