In sugar water, the ratio of sugar to water is 1:4. What is the concentration of this glass of sugar water?
糖水中，糖和水的比是1：4，这杯糖水的浓度是多少．
<gadget id="calculator">1 + 4</gadget>
<output>5</output>

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

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