What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

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.

Solve below popular number sequence
314 159 265 358 979 323 846 ?

Jenifer is learning to drive her car. She went down a one way lane and in the wrong direction. But she do not break any law.

How come ?

Analyze and find the missing item in the sequence:
16, 06, 68, 88, __, 98

I never stop running even when I standstill. If I am formed by joining two identical bodies together, can you guess who I am?

There are three boxes on a table. One of the box contains Gold and the other two are empty. A printed message contains in each box. One of the message is true and the other two are lies.

The first box says "The Gold is not here".

The Second box says "The Gold is not here".

The Third box says "The Gold is in the Second box".

Which box has the Gold?

I come in different shapes and sizes.
Parts of me are curved, other parts are straight.
You can put me anywhere you like,
but there is only one right place for me.
What am I?

If there are fifteen crows on a fence and the farmer shoots a third of them, how many crows are left?