There are 25 passengers on a bus. When it arrives at the stop, 8 passengers get off and 13 passengers get on. How many passengers are there in total?
一辆公交车上有25名乘客，到站点时下去了8名乘客，又上来13名乘客，这时车上共有多少名乘客？
<gadget id="calculator">25 - 8</gadget>
<output>17</output>

<gadget id="calculator">17 + 13</gadget>
<output>30</output>

<result>30</result>