Qingshan Primary School uses 160 tons of water in September and 140 tons in October. How much water is saved in October compared to September?
青山小学九月份用水160吨，十月份用水140吨，十月份比九月份节约用水百分之几？
<gadget id="calculator">160 - 140</gadget>
<output>20</output>

<gadget id="calculator">20 / 160</gadget>
<output>1/8 = around 0.125</output>

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