Replace the question mark with the correct number.

2 + 2= 4
3 + 3= 18
4 + 4= 48
5 + 5= ?

John and Jacob are twin brothers. One of them is a liar whereas the other one is a truth-teller.

I called their home number and one of them picked up.
I asked. 'Does John lie?' The person replied with a yes.

Whom did I talk with, John or Jacob?

You want to boil a two-minute egg. If you only have a three-minute timer (hourglass), a four-minute timer and a five-minute timer, how can you boil the egg for only two minutes?

Solve the mathematical equation in the picture below.

How many letters are in the alphabet?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

How will you measure 15 minutes using two hourglasses of 7 minutes and 11 minutes respectively?

Can you find the thief by just looking at the picture below?

A man and a dog were going down the street. The man rode, yet walked. What was the dog’s name?

Here is a conversation between a couple who both are software professionals.

Husband: Hey! What is your date of birth?
Wife Replied Angrily: It is 591062400
Husband after doing some calculations replied, "Got It".

What is the DOB of the wife?