Dad took Xiao Ming to climb the mountain on weekends. It took them 3 hours to go up the mountain and 2.5 hours to go down the mountain. The average speed of going up and down the mountain was 2.88 kilometers per hour. How far is the distance from the bottom of the mountain to the top of the mountain?
双休日爸爸带小明去登山，他们上山用了3小时，下山用了2.5小时，上、下山的平均速度是每小时走2.88千米，从山底到山顶的距离有多远？
<gadget id="calculator">3 + 2.5</gadget>
<output>5.5</output>

<gadget id="calculator">5.5 / 2</gadget>
<output>2.75</output>

<gadget id="calculator">2.88 * 2.75</gadget>
<output>7.92</output>

<result>7.92</result>