factory used 75 tons of water in June, saving 21 tons compared with May. What percentage did you save?
某工厂六月份用水75t，比五月份节约21t．节约了百分之几？
<gadget id="calculator">75 + 21</gadget>
<output>96</output>

<gadget id="calculator">21 / 96</gadget>
<output>7/32 = around 0.21875</output>

<result>7/32 = around 0.21875</result>