In a long-distance bus, (2/7) passengers get off halfway, and 12 people get on the bus. At this time, the ratio of the number of passengers on the bus to the original number of passengers is 13:14. How many passengers were there in this bus?
一辆长途汽车，中途有(2/7)乘客下车，又有12人上车，这时车上的乘客与原来的乘客人数比是13：14，这辆车上原来有乘客多少人？
<gadget id="calculator">13 / 14</gadget>
<output>13/14 = around 0.928571</output>

<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">1 - (2/7)</gadget>
<output>5/7 = around 0.714286</output>

<gadget id="calculator">(13/14) - (5/7)</gadget>
<output>3/14 = around 0.214286</output>

<gadget id="calculator">12 / (3/14)</gadget>
<output>56</output>

<result>56</result>