Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

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

81 x 9 = 801. What must you do to make the this equation true?

There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?

Find out a multi-digit number that if multiplied by the number 9 or any of its multiplications products (i.e. 18, 27, 36, 45,..) will result in the multiplication factor repeated (n) number of times.

1 dollar = 100 cent
= 10 cent x 10 cent
= 1/10 dollar x 1/10 dollar
= 1/100 dollar
= 1 cent

=> 1 dollar = 1 cent

solve this tricky problem?

I shave every day, but my beard stays the same. What am I?

Can you find out the remainder when 3^300 is divided by 5?

Queen Elizabeth organised a royal party.

To Avoid uninvited guest royal family set a password.
Jack (an uninvited person) plan to enter the party. He stand nearby the door.

First guest comes, the security person said 'twelve' and guest replied with six.
Second guest comes , the security person said 'six' and guest replied with 'three'.

Jack thought is enough and he walked to the entry point. The security person said 'eight' , Jack replied smilingly 'four'.
He was immediately thrown out of the party. why ?

I cannot talk, but I always reply when spoken to. What am I?