Three doctors said that Bill was their brother. Bill says he has no brothers. How many brothers does Bill actually have?

A man dies of old age on his 25 birthday. How is this possible?

If an earthquake is 1 point higher on the Richter Scale than another earthquake which is actually 10 times stronger, how much stronger would an earthquake be if it was just half a point higher on the Richter scale?

Find the number of squares in the below picture

What always comes into a house through the keyhole?

Identify Me

Hint1: I am a god
Hint 2: I am a planet
Hint 3: measurer of heat

Three friends named Mr. Black, Mr. Yellow and Mr. Green enter a pub on a weekend night. They are wearing either a Black, Yellow or Green shirt.

Mr. Yellow says to them, 'Did you notice that we all are wearing different color shirts than our names?'

To this, the man who was wearing the Green shirt said. 'Wow, thats right.'

Can you identify who is wearing which colour shirt ?

I make a loud sound when I’m changing. When I do change, I get bigger but weigh less. What am I?

Which Burger Is Different in below image?

You are given four results as below:
1111 = F
2222 = E
3333 = T
Then, can you find out how to code 4444?