Last year, the livestock farm raised 20% fewer cattle than this year. This year it raised 120 cattle. How many cattle did it raise last year?
畜牧场去年养牛比今年少20%，今年养牛120头，去年养牛多少头？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">120 * (4/5)</gadget>
<output>96</output>

<result>96</result>