A highway is 8,000 meters long. 30% of the total length was repaired on the first day, and 50% of the total length was repaired on the second day. How many meters are left to be repaired?
一条公路长8000米，第一天修了全长的30%，第二天修了全长的50%，还剩多少米没有修？
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 - (3/10) - (1/2)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">8_000 * (1/5)</gadget>
<output>1_600</output>

<result>1_600</result>