A book has 160 pages. I read (1/4) of it for the first time, and the remaining 40% for the second time. How many pages are left?
一本书160页，第一次看了它的(1/4)，第二次看了余下的40%，还剩多少页没有看？
<gadget id="calculator">1 / 4</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">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(3/4) * (2/5)</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (1/4) - (3/10)</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">160 * (9/20)</gadget>
<output>72</output>

<result>72</result>