I’m tall when I’m young, and I’m short when I’m old. What am I?

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

10 people came into a hotel with 9 rooms and each guest wanted his own room. The bellboy solved this problem.
He asked the tenth guest to wait for a little with the first guest in room number 1. So in the first room, there were two people. The bellboy took the third guest to room number 2, the fourth to number 3, ..., and the ninth guest to room number 8. Then he returned to room number 1 and took the tenth guest to room number 9, still vacant.
How can everybody have his own room?

A mathematician couple was having a Frappuccino in Starbucks sitting opposite to each other. Suddenly the guy noticed the text written on the paper in front of them and exclaimed that it was wrong. The girl denied it and said it is appropriate. Both are correct. What is written on the paper?

There are 2 people near the river and both of them want to get on the other side. The boat can only take one of them. But they got across.
How?

An equation has been laid down using a few matchsticks. However, as you can see, the equation is not correct. Can you correct the equation if you are allowed to add or remove 5 matchsticks?

Why do Chinese men eat more rice than Japanese men do ?

A red house is made out of red bricks. A yellow house is made out of yellow bricks. And, a blue house is made out of blue bricks. So, what is a greenhouse made of?

Through your logical capabilities, can you make 7 an even?

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