3. Linglong Tower has 7 floors, and there is a direct elevator in the tower. Qisi and Wangwang go sightseeing from the 1st floor to the 7th floor. Qisi chooses to wait in line for the elevator, while Wangwang chooses to climb the stairs. When Wangwang reaches the 5th floor, Qisi finally gets on the elevator. In the end, both arrive at the 7th floor at the same time. The upward speed of the elevator is $\qquad$ times the speed of Wangwang climbing the stairs.
$3$