1 ton of rapeseed can extract (1/5) ton of oil, and to squeeze 6 tons of rapeseed oil, how many tons of rapeseed are needed.
1吨菜籽可榨油(1/5)吨，要榨6吨菜籽油，需要菜籽多少吨吨．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">6 / (1/5)</gadget>
<output>30</output>

<result>30</result>