A car happens to be full of people when it leaves the station. When it arrives at a station on the way, (1/4) of the passengers get off, and 21 people get on the car, and 6 passengers have no seats. Now, how many passengers are in the car?
一辆汽车从车站开出时恰好坐满了人，途中到达某站，有(1/4)的乘客下车，又有21人上车，有6位乘客没有座位．现在，车内有乘客多少人？
<gadget id="calculator">21 - 6</gadget>
<output>15</output>

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

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">15 / (3/4)</gadget>
<output>20</output>

<gadget id="calculator">20 + 6</gadget>
<output>26</output>

<result>26</result>