Replace the question mark with the correct number.

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?

An explorer goes on an exposition in the jungle. He sets up camp in the middle of the jungle. The next morning he sees something with a head and a tail, but he is not afraid. What did he see in his bag?

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

What is red and smells like blue paint?

John went to buy some expensive, foreign chocolates. He only had Rs 100 with him. When he reached the shop, he got out and know that on those chocolates, there was a 15% import duty and 5% VAT.

How much worth chocolate should he buy so that he can accommodate it in Rs 100?

Why are televisions attracted to people?

John was born on March 5, 1970, in Delhi, India. Jacob was born 25 days before John. The year when they took birth, Republic Day fell on Monday.

Can you find out on what day was Jacob born?

How can you write nineteen in a manner that if we take out one, it becomes twenty?