In the aquarium of the park, 390 red goldfish are stocked, and the number of flower goldfish is twice that of red goldfish. How many flower goldfish are there?
公园的养鱼池里，放养红金鱼390条，放养花金鱼的条数是红金鱼的2倍，花金鱼有多少条？
<gadget id="calculator">390 * 2</gadget>
<output>780</output>

<result>780</result>