The ship sails from port A to port B, and travels 28 kilometers per hour along the water. When returning to port A, it takes 6 hours to travel against the current. It is known that the water speed is 4 kilometers per hour. How many kilometers are there between the two ports?
轮船从甲港开往乙港，顺水而行每小时行28千米，返回甲港时逆水而行用了6小时，已知水速是每小时4千米，甲乙两港相距多少千米？
<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<gadget id="calculator">28 - 8</gadget>
<output>20</output>

<gadget id="calculator">20 * 6</gadget>
<output>120</output>

<result>120</result>