It takes Xiao Ming 60 seconds to climb from the 1st floor to the 5th floor, so how many seconds does it take to go from the 1st floor to the 3rd floor?
小明从1楼爬到5楼用60秒，照这样从1楼到3楼用时多少秒．
<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">60 / 4</gadget>
<output>15</output>

<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">15 * 2</gadget>
<output>30</output>

<result>30</result>