There are 4000 sheets in a pack of paper, (5/8) are used up, how many sheets are left?
一包纸有4000张，用去了(5/8)，还剩下多少张？
<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">1 - (5/8)</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">4_000 * (3/8)</gadget>
<output>1_500</output>

<result>1_500</result>