Two people, A and B, compete to climb the stairs from the first floor, and the speed of A climbing the stairs is 1.5 times that of B. They set off at the same time, when A climbed to the 16th floor, on what floor was B?
甲、乙两人从一楼开始比赛爬楼梯，甲爬楼梯的速度是乙的1.5倍．他们同时出发，当甲爬到16楼时，乙在多少楼．
<gadget id="calculator">16 - 1</gadget>
<output>15</output>

<gadget id="calculator">15 / 1.5</gadget>
<output>10</output>

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

<result>11</result>