The convoy slowly passes a 200-meter-long bridge at a speed of 4 m/s, taking 115 seconds. It is known that each vehicle is 5 meters long and the distance between two vehicles is 10 meters. How many vehicles are there in this convoy?
车队以4米/秒的速度缓缓通过一座长200米的大桥，共用秒115，已知每辆车长5米，两车间隔10米，这个车队共有多少辆车．
<gadget id="calculator">4 * 115</gadget>
<output>460</output>

<gadget id="calculator">460 - 200</gadget>
<output>260</output>

<gadget id="calculator">10 + 260</gadget>
<output>270</output>

<gadget id="calculator">5 + 10</gadget>
<output>15</output>

<gadget id="calculator">270 / 15</gadget>
<output>18</output>

<result>18</result>