There are 274 species of fish that can be named in the waters of the Yangtze River, which is about 80 species less than the national freshwater fish species (1/2). How many kinds of freshwater fish are there in the country? (column equation solution)
长江水域中能说出名称的鱼有274种，约比全国淡水鱼种类的(1/2)少80种．全国淡水鱼有多少种？(列方程解答)
<gadget id="calculator">80 + 274</gadget>
<output>354</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">354 / (1/2)</gadget>
<output>708</output>

<result>708</result>