You can see that square root or 22 is between sqrt (16)=4 and sqrt(25)=5 so will be 4.something
We can also see that between 16 and 25 there are 9 spaces that is about 10
if we go from 16 towards 22 we need to pass 6 spaces that are worth .10 there fore
Sqrt (22) is about 4.60