A horse weighs 0.45 tons, a hippopotamus weighs as much as 3 horses, and an elephant weighs 6 times as much as a hippopotamus. How many tons does an elephant weigh?
一匹马重0.45吨，一头河马的重量相当于3匹马的重量，一头大象的重量是一头河马的6倍，一头大象重多少吨？
<gadget id="calculator">0.45 * 3 * 6</gadget>
<output>8.1</output>

<result>8.1</result>