The school used 160 tons of water in April, saving 40 tons of water compared to March, and how many percent was saved compared to March?
学校四月份用水160吨，比三月份节约用水40吨，比三月份节约百分之几？
<gadget id="calculator">160 + 40</gadget>
<output>200</output>

<gadget id="calculator">40 / 200</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>