Replace the question mark with the correct number below.

What do you answer even though it never asks you questions?

I am the fastest animal but cannot climb the tree. What am I?

Can you solve this picture maths equation?

A mother is 21 years older than her child. In exactly 6 years from now, the mother will be exactly 5 times as old as the child.
Where's the father?

Three people enter a room and have a green or blue hat placed on their heads. They cannot see their own hat but can see the other hats.
The colour of each hat is purely random. They could all be green, blue, or any combination of green and blue.
They need to guess their own hat colour by writing it on a piece of paper, or they can write 'pass'.
They cannot communicate with each other in any way once the game starts. But they can have a strategy meeting before the game.
If at least one of them guesses correctly they win $10,000 each, but if anyone guesses incorrectly they all get nothing.
What is the best strategy?

Identify the 10 differences between the two given pictures.

What can run but never walks, has a mouth but never talks, has a head but never weeps, has a bed but never sleeps?

What is the word or phrase below?
R | E | A | D

Rearrange the letters in "new door" to make one word.