The tortoise and the hare run a 10,000-meter race. The speed of the rabbit is five times that of the tortoise. When they start from the starting point, the tortoise keeps running. The rabbit goes to a certain place and starts to sleep. When the rabbit wakes up, the tortoise is 5,000 meters ahead of it. The rabbit rises up Go straight to catch up, but when the tortoise reaches the finish line, the rabbit is still 100 meters behind, so how many meters did the tortoise run while the rabbit was sleeping?
龟兔进行10000米赛跑，兔子速度是乌龟的5倍，当它们从起点出发后，乌龟不断地跑，兔子跑到某一地点开始睡觉，兔子醒来时，乌龟已经领先它5000米，兔子奋起直追，但乌龟到达终点时，兔子仍落后100米，那么在兔子睡觉期间，乌龟跑了多少米．
<gadget id="calculator">10_000 - 100</gadget>
<output>9_900</output>

<gadget id="calculator">9_900 / 5</gadget>
<output>1_980</output>

<gadget id="calculator">10_000 - 1_980</gadget>
<output>8_020</output>

<result>8_020</result>