There are two trains, one is 130m long and the speed is 23m/s; the other is 250m long and the speed is 15m/s. Now two cars are going towards each other, how many s are needed from meeting to leaving.
有两列火车，一车长130m，速度为23m/s；另一列火车长250m，速度为15m/s．现在两车相向而行，从相遇到离开需要多少s．
<gadget id="calculator">130 + 250</gadget>
<output>380</output>

<gadget id="calculator">23 + 15</gadget>
<output>38</output>

<gadget id="calculator">380 / 38</gadget>
<output>10</output>

<result>10</result>