ton of rapeseed can extract (2/5) tons of oil. According to this calculation, how many tons of oil can be extracted from a ton of rapeseed.
1吨菜子可以榨油(2/5)吨，照这样计算，a吨菜子可以榨油多少吨．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>