tejal777 wrote:

2 sizes of sticky pads. Each has 4 colors - Blue, Green, Yellow, and Purple. The pads are packed in packages that contain either 3 notepads of same size and same color or 3 notepads of same size and of 3 different colors. How many different packages of the types described are possible?

a. 6

b. 8

c. 16

d. 24

e. 32

Okay, calm down tejal... keeping head cool is the key... This problem is very easy if you employ the correct approach and here is the right one:

Packages can be prepared in following 2 ways:

1) 3 notepads of same size and same color

2) 3 notepads of same size and of 3 different colors

Lets go step by step.

1) 3 notepads of same size and same color:

We know that there are 2 sizes of pads and 4 colors in total. We want to keep the size and color same. so there are 2*4 = 8 ways to create package.

2) 3 notepads of same size and of 3 different colors:

We want to select 3 colors out of 4 available = 4C3 = 4

And there are 2 sizes of notepad available. So the total ways in which a package can be created is = 4C3*2 = 8

So total 8+8 = 16 packages can be created. Answer is C.

Questions? Bring them on