Just list, do not count: the cafeteria used 21 tons of coal in July, saving 3 tons compared with June, what percentage was the saving?
只列式，不计算：食堂七月份用煤21吨，比六月份节约3吨，节约了百分之几？
<gadget id="calculator">21 + 3</gadget>
<output>24</output>

<gadget id="calculator">3 / 24</gadget>
<output>1/8 = around 0.125</output>

<result>1/8 = around 0.125</result>