The mass ratio of hydrogen and oxygen in water is 1:8, how many kilograms of hydrogen are contained in 378 kilograms of water.
氢和氧在水中的质量比是1﹕8，378千克水中含有氢多少千克．
<gadget id="calculator">1 + 8</gadget>
<output>9</output>

<gadget id="calculator">1 / 9</gadget>
<output>1/9 = around 0.111111</output>

<gadget id="calculator">378 * (1/9)</gadget>
<output>42</output>

<result>42</result>