It takes 6 hours to travel from East Port to West Port, and it takes 4 hours for Ship B to travel from West Port to East Port. Now the two ships depart from the East and West ports at the same time and head toward each other, and finally meet at a distance of 18 kilometers from the midpoint. How many kilometers is the distance between the East and West ports?
从东港到西港要6小时，乙船从西港到东港要4小时，现在两船同时从东西两港出发相向而行，结果在离中点18千米处相遇．问东西两港相距多少千米？
<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(3/5) - (2/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">2 / (1/5)</gadget>
<output>10</output>

<gadget id="calculator">18 * 10</gadget>
<output>180</output>

<result>180</result>