The ratio of chickens to ducks in Uncle Wang’s family is 5:3. If there are 150 chickens, how many ducks are there?
王大爷家养鸡和鸭的只数比是5：3，如果养鸡150只，那么养鸭多少只？
<gadget id="calculator">150 / 5</gadget>
<output>30</output>

<gadget id="calculator">30 * 3</gadget>
<output>90</output>

<result>90</result>