A pile of 400 tons of sand is transported away on the first day (5/8), and 100 tons on the second day, how many tons are left?
一堆沙400吨，第一天运走(5/8)，第二天运走100吨，还剩下多少吨？
<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">400 * (5/8)</gadget>
<output>250</output>

<gadget id="calculator">400 - 250 - 100</gadget>
<output>50</output>

<result>50</result>