It took Grandma Li 12 minutes to climb from the first floor to the fourth floor. At this speed, how many minutes would it take from the first floor to the seventh floor?
李奶奶从一楼爬到四楼用了12分钟，照这样的速度，一楼到七楼需要多少分钟．
<gadget id="calculator">7 - 1</gadget>
<output>6</output>

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

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

<gadget id="calculator">6 * 4</gadget>
<output>24</output>

<result>24</result>