small river flows through towns A, B, and C. A steamboat travels between towns A and B, and the speed of the steamboat in still water is 11 kilometers per hour. There is a wooden boat ferry between towns B and C, and the speed of the wooden boat in still water is 3.5 kilometers per hour. It is known that the waterways of towns A and C are 50 kilometers apart, and the water velocity is 1.5 kilometers per hour. A person goes down the river from town A to town B by steamboat. It takes 1 hour to have lunch, and then goes down the river to town C by wooden boat. It takes 8 hours. What is the distance in meters between towns A and B? ．
一条小河流过A、B、C三镇．A、B两镇之间有汽船来往，汽船在静水的速度为每小时11千米．B、C两镇之间有木船摆渡，木船在静水中的速度为每小时3.5千米．已知A、C两镇水路相距50千米，水流速度为每小时1.5千米．某人从A镇上乘汽船顺流而下到B镇，吃午饭用去1小时，接着乘木船又顺流而下到C镇，共用8小时，那么A、B两镇的水路路程是多少米．
<gadget id="calculator">50 / 5</gadget>
<output>10</output>

<gadget id="calculator">10 - 7</gadget>
<output>3</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 / 12.5</gadget>
<output>0.08</output>

<gadget id="calculator">(1/5) - 0.08</gadget>
<output>0.12</output>

<gadget id="calculator">3 / 0.12</gadget>
<output>25</output>

<gadget id="calculator">25 * 1_000</gadget>
<output>25_000</output>

<result>25_000</result>