For a pile of 80 tons of yellow sand, 25% was removed on the first day, 4 tons more than on the second day. How many tons are left?
一堆黄沙80吨，第一天运走25%，比第二天多运4吨．还剩下多少吨？
<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">80 * (1/4)</gadget>
<output>20</output>

<gadget id="calculator">20 - 4</gadget>
<output>16</output>

<gadget id="calculator">80 - 20 - 16</gadget>
<output>44</output>

<result>44</result>