Verbal Reasoning - Mental Ability Questions

All except roof are dwelling places of different animals.

The sequence in first column is x 5. Thus, 1 x 5 = 5,  5 x 5 = 25,  25 x 5 = 125.
The sequence in third column is x 2. Thus, 7x 2 = 14,  14 x 2 = 28,  28 x 2 = 56.
The sequence in second column is x 4.
.'. Missin number = 12 x 4 = 48.

Points that lie on the same line are called Collinear points. And that points lie on the same plane are called Coplanar points. 

Binary system is what the representation uses only two digits 0 & 1.

It uses only the powers of 2.

6 choose 3 means number of possible unordered combinations when 3 items are selected from 6 available items i.e, nothing but 6C3.

Now 6C3 = 6 x 5 x 4/3 x 2 x 1 = 120/6 = 20.