According to the question,
Number of storeys between 106th and 46th floor = 106 - 46 = 60 floors
Total height of 60 floors = 60 x 5 = 300m
Now, we know that the lift moves 3m every second.
So, time taken to travel 300m = 300/3
= 100 seconds
= 1 min 40 sec
Hope that helps !!