It took Xiao Ming 18 seconds to walk from the first floor to the third floor. At this speed, how many seconds would it take him to walk from the first floor to the fifth floor?
小明从一楼走到三楼用了18秒，照这样的速度，他从一楼走到五楼要用多少秒．
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">18 / 2</gadget>
<output>9</output>

<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">9 * 4</gadget>
<output>36</output>

<result>36</result>