There were originally 28 passengers on a bus, but when it arrived at the camel station, 12 got off and 16 got on again. How many more passengers are there in the car now than before?
一辆公交车上原来有乘客28人，到骆驼站时，下车12人，又上车16人．现在车上的乘客比原来多多少人．
<gadget id="calculator">28 - 12</gadget>
<output>16</output>

<gadget id="calculator">16 + 16</gadget>
<output>32</output>

<gadget id="calculator">32 - 28</gadget>
<output>4</output>

<result>4</result>