5 cats eat 5 fish in 5 days, how many fish do 20 cats eat in 20 days?
5只猫5天吃5条鱼，20只猫20天吃多少条鱼．
<gadget id="calculator">20 / 5</gadget>
<output>4</output>

<gadget id="calculator">5 * 4 * 4</gadget>
<output>80</output>

<result>80</result>