A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?

Six people park their car in an underground parking of a store. The store has six floors in all. Each one of them goes to a different floor. Simon stays in the lift for the longest. Sia gets out before Peter but after Tracy. The first one to get out is Harold. Debra leaves after Tracy who gets out on the third floor.

Can you find out who leaves the lift on which floor?

In a science lab, a petri dish hosts a healthy colony of yeast for an experiment. Now every minute, all the yeast cells divide into two. At noon, there was just a single cell of yeast and at 1:22, the Petri dish was half full. Can you calculate when the dish will be full of yeast?

A word I know has six letters it contains, remove one letter and 12 remain. What is it?

You are a cab driver who pools passengers. You pick 3 people from a destination and drop 1 after an hour. 2 people climb aboard at the same time and you drop 3 at the next destination. After some time, you pick 2 passengers only to drop 1 after a short distance where 3 more passengers climb up the cab. You leave the rest of the passengers one by one to their destination and then come back home.

Can you tell the eye color of the cab driver?

2 ladies and 2 girls need to cross a river in a boat big enough for 1 LADY or 2 girls. How do they do it?

If six children and two dogs were under an umbrella, how come none of them got wet?

Can you find the hidden animal in the picture below?

You are given four results as below:
1111 = F
2222 = E
3333 = T
Then, can you find out how to code 4444?

It has horns but can’t beep. It is like to bleat but It is not a sheep. What is it?