Koizumi rowed a small boat at a fixed speed on a small river. He rowed along the current for 2 hours, and then rowed against the current to return to the original starting point. It took him 3 hours. The velocity of the water in this river is known to be 2 km/h. So what is the distance in kilometers between Koizumi's starting point and the point where he started to return.
小泉在一条小河上以固定的速度划一条小船，他顺流划行了2小时，然后逆流划行返回到原来的出发地点，用了3小时．已知这条河的水流速度是2千米/时．那么小泉的出发地点与他开始返回的地点之间的距离是多少千米．
<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<gadget id="calculator">3 * 2</gadget>
<output>6</output>

<gadget id="calculator">4 + 6</gadget>
<output>10</output>

<gadget id="calculator">3 - 2</gadget>
<output>1</output>

<gadget id="calculator">10 / 1</gadget>
<output>10</output>

<gadget id="calculator">10 + 2</gadget>
<output>12</output>

<gadget id="calculator">2 * 12</gadget>
<output>24</output>

<result>24</result>