A basket of fresh fish, the weight of the basket is 56 kg, half of the fresh fish is sold first, and the weight of the basket is 30 kg. So how many kilograms of the original fresh fish.
一筐鲜鱼，连筐的重量是56千克，先卖掉鲜鱼的一半，这时连筐还重30千克．那么原有鲜鱼多少千克．
<gadget id="calculator">56 - 30</gadget>
<output>26</output>

<gadget id="calculator">26 * 2</gadget>
<output>52</output>

<result>52</result>