It took Xiao Ming 8 seconds to walk from the first floor to the third floor. How many seconds would it take him to walk from the first floor to the fourth floor?
小明从一楼走到三楼用了8秒，照这样他从一楼走到四楼要多少秒．
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">4 - 1</gadget>
<output>3</output>

<gadget id="calculator">4 * 3</gadget>
<output>12</output>

<result>12</result>