Fresh water accounts for 2.7% of the total water resources of the earth, of which usable fresh water accounts for 25% of the total fresh water.
地球水资源总量中淡水占2.7%，其中可使用淡水占淡水总量的25%，可使用淡水占地球水资源总量的多少．
<gadget id="calculator">2.7 / 100</gadget>
<output>0.027</output>

<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">0.027 * (1/4)</gadget>
<output>0.00675</output>

<result>0.00675</result>