Each basketball in the supermarket is 24 yuan. Mom bought 3 basketballs and paid 100 yuan. How much should I get back?
超市每个篮球24元，妈妈买了3个篮球，付了100元，应找回多少元？
<gadget id="calculator">3 * 24</gadget>
<output>72</output>

<gadget id="calculator">100 - 72</gadget>
<output>28</output>

<result>28</result>