The weight of a goose is equal to the weight of 2 ducks, and the weight of 3 ducks is equal to the weight of 15 pigeons. The weight of a goose is equal to the weight of pigeons.
一只鹅的重量相当于2只鸭的重量，3只鸭的重量等于15只鸽子的重量．一只鹅的重量相当于多少只鸽子的重量．
<gadget id="calculator">2 * 5</gadget>
<output>10</output>

<result>10</result>