Litchi and lotus mist are 100kg in total. After half of each is sold, 50kg of lotus mist is transported in. At this time, their ratio is 1:4. How much more is the lotus mist than litchi?
荔枝和莲雾共100kg，各卖出一半后，又运进莲雾50kg，此时它们的比是1：4，莲雾比荔枝多多少千克？
<gadget id="calculator">5 / 2</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">100 / (5/2)</gadget>
<output>40</output>

<gadget id="calculator">100 - 40</gadget>
<output>60</output>

<gadget id="calculator">60 - 40</gadget>
<output>20</output>

<result>20</result>