There is a passenger ship carrying passengers, sailing from Shanghai to Guangzhou via Xiamen and Shantou. The passengers who disembarked in Xiamen accounted for (1/3) of the total number of passengers on board, while the number of new passengers who boarded was 73; the passengers who disembarked in Shantou accounted for (3/5) of the total number of passengers on board at that time, while the number of new passengers who boarded was 80; when the ship arrived in Guangzhou, all passengers disembarked, which was exactly half of the total number of passengers when it set sail from Shanghai. Then how many passengers were there when it set sail in Shanghai?
有一客轮载乘客，由上海启航经厦门、汕头两站去广州．在厦门下船的乘客为船上乘客总数的(1/3)，而上船的新乘客为73名；在汕头下船的乘客为当时船上乘客总数的(3/5)，而上船的新乘客为80名；船到广州后，全部乘客都下船，恰为上海启航时乘客总数的一半．则在上海启航时共有多少名乘客．
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 - (3/5)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">73 * (2/5)</gadget>
<output>146/5 = around 29.2</output>

<gadget id="calculator">(146/5) + 80</gadget>
<output>546/5 = around 109.2</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (1/3)</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">(2/3) * (2/5)</gadget>
<output>4/15 = around 0.266667</output>

<gadget id="calculator">(1/2) - (4/15)</gadget>
<output>7/30 = around 0.233333</output>

<gadget id="calculator">(546/5) / (7/30)</gadget>
<output>468</output>

<result>468</result>