The elementary school of the public school uses 320 tons of water in September and 280 tons of water in October. How much water is saved in October compared to September?
公学小学部9月份用水320吨，10月份用水280吨，10月份比9月份节约用水多少．
<gadget id="calculator">320 - 280</gadget>
<output>40</output>

<gadget id="calculator">40 / 320</gadget>
<output>1/8 = around 0.125</output>

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