How will you measure 15 minutes using two hourglasses of 7 minutes and 11 minutes respectively?

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

A newspaper is supposed to have 60 pages.Pages 14 and 21 are missing from the newspaper.

Can you tell me , Which other pages won't be there as well ?

A professor thinks of two consecutive numbers between 1 and 10.
'A' knows the 1st number and 'B' knows the second number

A: I do not know your number.
B: Nor do I know your number.
A: Now I know.

What are the four solutions for this?

It's pretty hard to give up.
If you remove a part of it, you will be left with a bit.
Even if you remove another part, the bit still remains.
Remove one more and it still remains.

What is it?

I am lying and I always lie. Tell me whether I am lying or telling the truth.

Can you find out the number that should replace the question mark with a valid reason?

Paul's height is six feet, he's an assistant at a butcher's shop and wears size 9 shoes. What does he weigh?

Prove that twice of ten is the same as twice of eleven.

I make two people out of one. What am I?