The salesman Xiao Li wants to go to the sixth floor to contact work. It took him 54 seconds to go from the first floor to the fourth floor. According to this calculation, how many seconds will it take for Xiao Li to reach the sixth floor.
业务员小李要到六楼联系工作，他从1楼到4楼用了54秒，照这样计算，小李走到6楼还需要多少秒．
<gadget id="calculator">4 - 1</gadget>
<output>3</output>

<gadget id="calculator">54 / 3</gadget>
<output>18</output>

<gadget id="calculator">6 - 4</gadget>
<output>2</output>

<gadget id="calculator">18 * 2</gadget>
<output>36</output>

<result>36</result>