Mom puts some toffee and fruit sugar in small bags, and each bag is filled with 0.25 kg of toffee and 0.15 kg of fruit sugar. When 4.5 kilograms of fruit sugar is used, how many kilograms of milk sugar are used?
妈妈将一些奶糖和水果糖分装在小袋里，每袋装入0.25千克奶糖和0.15千克水果糖．当水果糖用去4.5千克时，用去奶糖多少千克？
<gadget id="calculator">4.5 / 0.15</gadget>
<output>30</output>

<gadget id="calculator">30 * 0.25</gadget>
<output>7.5</output>

<result>7.5</result>