A new high-rise building is built, with the same number of steps on each floor, and the speed of Dad going up the stairs is twice that of Xiao Ming. One day, because the elevator was being repaired, they walked up from the first floor at the same time. When Xiao Ming reached the sixth floor, which floor did Dad go?
新建一幢高楼，每层台阶一样多，爸爸上楼的速度是小明速度的2倍．一天，由于电梯正在修理，所以他们同时从一楼往上走，小明到达6楼时，爸爸走到几楼？
<gadget id="calculator">6 - 1</gadget>
<output>5</output>

<gadget id="calculator">5 * 2</gadget>
<output>10</output>

<gadget id="calculator">10 + 1</gadget>
<output>11</output>

<result>11</result>