Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

Cristina was born in 1888. She just had her 30th birthday today how did that happen?

Nine marbles are arranged in the image below. Can you slide two marbles to form a square?

What jumps when it walks and sits when it stands?

In the image below, can you find the value of an angle(y)

I have a mouth but I don't eat.
I have a bank but have no money.
I have a bed but i dont sleep.
I wave but have no hands.

Who Am I ?

I am a normal creature, but I have five hands. I can even have more but even then I will be considered normal.

Who am I?

Can you decipher these quotes by Albert Einstein?
Blf xzm mvevi hloev z kilyovn lm gsv ovevo lm dsrxs rg dzh xivzgvw.

It's a protector.
It sits on a bridge.
One individual can see directly through it, while others wonder what it hides.

What is it?

Can you find the mistake in the below statement?