3 cats can catch 3 mice in 3 days, how many cats are needed to catch 200 mice in 100 days?
3只猫3天能捉3只老鼠，照这样计算，要在100天里捉200只老鼠需要多少只猫．
<gadget id="calculator">200 / 100</gadget>
<output>2</output>

<gadget id="calculator">2 * 3</gadget>
<output>6</output>

<result>6</result>