For one inspection, there are 30 floats in a convoy to be inspected, each of which is 4 meters long, and the distance between the front and rear cars is 5 meters. If the convoy travels 2 meters per second, how long will it take for the convoy to pass through the 535-meter-long parade field?
一次检阅，接受检阅的一列彩车车队共30辆，每辆车长4米，前后两辆车相隔5米．如果车队每秒行驶2米，那么这列车队要通过535米长的检阅场地，需要多少时间？
<gadget id="calculator">30 * 4</gadget>
<output>120</output>

<gadget id="calculator">30 - 1</gadget>
<output>29</output>

<gadget id="calculator">29 * 5</gadget>
<output>145</output>

<gadget id="calculator">120 + 145 + 535</gadget>
<output>800</output>

<gadget id="calculator">800 / 2</gadget>
<output>400</output>

<result>400</result>