There are 50 bulls in a cattle farm, and twice as many cows as bulls. How many cattle are there in total?
养牛场养公牛50头，母牛是公牛的2倍，养牛场共养牛多少头？
<gadget id="calculator">50 * 2</gadget>
<output>100</output>

<gadget id="calculator">50 + 100</gadget>
<output>150</output>

<result>150</result>