Uncle Li bought 4 sheep and spent 100 yuan. He wants to buy 8 more sheep of this kind. How much more money does he need to prepare?
李大爷买了4只羊，用了100元，他还想再买8只这种羊，需要再准备多少钱？
<gadget id="calculator">100 / 4</gadget>
<output>25</output>

<gadget id="calculator">25 * 8</gadget>
<output>200</output>

<result>200</result>