It takes Xiaolei 48 seconds to go from the 1st floor to the 4th floor, and Xiaohu takes 96 seconds to go from the 1st floor to the 5th floor. Xiaolei and Xiaohu go upstairs at the same time from the ground floor. When Xiaolei reaches the 19th floor, how many floors does Xiaohu go to?
小雷从1层到4层要用48秒钟，小虎从1层到5层要用96秒钟．小雷和小虎同时从底楼开始上楼，当小雷走到19层时，小虎走到了几层？
<gadget id="calculator">4 - 1</gadget>
<output>3</output>

<gadget id="calculator">48 / 3</gadget>
<output>16</output>

<gadget id="calculator">19 - 1</gadget>
<output>18</output>

<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">96 / 4</gadget>
<output>24</output>

<gadget id="calculator">18 / 24</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">16 * (3/4)</gadget>
<output>12</output>

<gadget id="calculator">12 + 1</gadget>
<output>13</output>

<result>13</result>