The price of eggs is 9.9 yuan per kilogram. Mom bought 2.5 kilograms and paid 50 yuan to the salesperson's aunt. How much should I get back?
鸡蛋的价格是每千克9.9元，妈妈买了2.5千克，付给售货员阿姨50元，应找回多少元？
<gadget id="calculator">9.9 * 2.5</gadget>
<output>24.75</output>

<gadget id="calculator">50 - 24.75</gadget>
<output>25.25</output>

<result>25.25</result>