Xiao Min reads a cartoon and reads 20 pages a day. After 6 days, 20% of the book remains. How many pages does this cartoon have?
小敏看一本卡通画，每天看20页，6天后还剩全书的20%，这本卡通画有多少页？
<gadget id="calculator">20 * 6</gadget>
<output>120</output>

<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">120 / (4/5)</gadget>
<output>150</output>

<result>150</result>