Xiaoyue and Dongdong went to play at Uncle Fei's house. Uncle Fei lived on the 15th floor. The two walked up from the first floor at the same time, and the speed remained the same. When Xiaoyue reached the third floor, Dongdong happened to be on the Layer 5. May I ask: When Dongdong walked to Uncle Fei's house, which floor did Xiaoyue go to?
小悦和冬冬去费叔叔家玩，费叔叔住在15层，两人同时从一楼往上走，速度都保持不变，当小悦走到第3层的时候，冬冬恰好走到第5层．请问：当冬冬走到费叔叔家的时候，小悦走到了第几层？
<gadget id="calculator">15 - 1</gadget>
<output>14</output>

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

<gadget id="calculator">3 - 1</gadget>
<output>2</output>

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

<gadget id="calculator">14 / 2</gadget>
<output>7</output>

<gadget id="calculator">7 + 1</gadget>
<output>8</output>

<result>8</result>