After eating 40% of a bag of rice, there is still 15 kg left. How much does the bag of rice weigh?
一袋大米吃掉40%后，还剩15千克，这袋大米重多少千克．
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">15 / (3/5)</gadget>
<output>25</output>

<result>25</result>