Replace the question mark with the number below given a simple math problem.

A Shopkeeper sold a few chickens to four different customers on a particular day. It was such that each customer purchased half of the remaining chickens and half the chicken more.

Can you find out how many chicken were sold by the shopkeeper on that day if we tell you that the fourth customer bought a single chicken ?

John bought a new car. He has a habit of eating ice cream from a particular ice cream shop while returning home from office. Whenever, he eats strawberry ice cream, he faces no problem. But whenever, he eats chocolate ice cream, the car starts giving problem. At first, he thinks, it is just a co-incidence but when this awkward incident happens for 3-4 times, he reports this problem to the company.

The mechanic of the company checks but finds no problem at all. The next day, when he stops by to eat chocolate ice cream, the car again starts giving problem.

Can you find the possible reason?

How many bricks does it take to complete a building that is 15 feet wide, 30 feet deep, and 12 feet tall made of brick?

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

I have a head like a cat and feet like a cat, but I am not a cat. What am I?

Irene killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

Speaking of rivers, a man calls his dog from the opposite side of the river. The dog crosses the river without getting wet, and without using a bridge or boat. How?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

If we tell you that there is a relation between the numbers and letters in the given figure, can you analyze it and find the missing letter in the last box?