Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

Can you find a pattern and the missing number in the series given below?

100, 155, 258,? , 584, 819.

John and Jenni are a married couple. They have two kids, one of them is a girl. Assume safely that the probability of each gender is 1/2.
What is the probability that the other kid is also a girl?

Hint: It is not 1/2 as you would first think.

Where do you go to learn how to make ice cream?

I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?

Known by all without exception, Forever here, for your protection, Sometimes strong, sometimes weak, Right after the night I come - hot and chic. And while millions of miles away, I always get to you, I find my way. No life around could do without me, Can you guess what I might be?

On a certain day, John celebrated his birthday. Two days later, his older twin brother Jacob celebrated his birthday.

Is this even possible? How can it be?

How many letters are in the alphabet?

By using 'because' continuously three times, can you make an English statement ?

Find the next number in the series

12, 20, 40, 72, 116, 172 ?