The number of science books is the number of story books (4/5), which means that the number of science books is much less than the number of story books
科技书的本数是故事书的(4/5)，也就是说科技书的本数比故事书少多少
<gadget id="calculator">5 - 4</gadget>
<output>1</output>

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

<result>1/5 = around 0.2</result>