Uncle Wang raised 98 sheep this year, an increase of 22.5% over last year. How many sheep were raised last year?
王大伯今年养了98只羊，比去年增加了22.5%，去年养羊多少只？
<gadget id="calculator">22.5 / 100</gadget>
<output>0.225</output>

<gadget id="calculator">1 + 0.225</gadget>
<output>1.225</output>

<gadget id="calculator">98 / 1.225</gadget>
<output>80</output>

<result>80</result>