In the city of Brain Teasers, 5% of people do not list their phone numbers. Now if we select random 100 people from the phone directory, then how many people selected will have unlisted phone numbers?

Given that

(78)^9 = 6
And (69)^4 = 11

Can you find out

(99)^2 =?

(Note: This is Logical, not Mathematical)

Can you find the ages of a son, father and grandfather based on the following facts?
The sum of the ages of grandfather, father and son is 140 years.
The age of the son in months is the same as the grandfather in years.
The age of the son in days is the same as the father in weeks.

What number comes next in the series?

5 15 5 18 5 24 14 20 _

Can you place three balls such that the equation shown in the picture holds true?

What is the Surname of Barbie Doll?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

Count the number of triangles in the picture below:

The day after tomorrow will be three days before Tuesday. Can you find out what is today?

This is a classy optical illusion puzzle. What more you can find except bricks in the image below?