passenger car is just full when it leaves station A. When it arrives at station B, (1/4) of the passengers get off and 15 people get on the bus. At this time, there are still 3 vacant seats on the bus. How many passengers are there in the car at this time.
一辆客车从甲站开出时刚好满座，到达乙站时，有(1/4)的乘客下车，又有15人上车，这时车上还有3个空位．这时车上有乘客多少人．
<gadget id="calculator">15 + 3</gadget>
<output>18</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">18 / (1/4)</gadget>
<output>72</output>

<gadget id="calculator">72 - 3</gadget>
<output>69</output>

<result>69</result>