Xiao Ming has 300 extra-curricular reading materials, which is 25% less than Xiao Liang's extra-curricular reading materials. How many extra-curricular reading materials does Xiao Ming have.
小明有课外读物300本，比小亮的课外读物的本数少25%，小亮有课外读物多少本．
<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">300 / (3/4)</gadget>
<output>400</output>

<result>400</result>