What is common among 11, 69, and 88?

Name one eight-letter word with 'kst' in the middle, 'in' the beginning, 'and' at the end.?

Take 9 from 6, 10 from 9, 50 from 40, and leave 6.

How Come ??

A container contains 100 eggs. They can be either fresh or rotten. What is sure is the fact that there is at least one fresh egg in that container.

If you are asked to pick two eggs randomly from the container, at least one of them will be rotten.

Can you calculate how many eggs in that container are fresh?

Two boys were admitted to a school. When the headmaster asks them about their parents, they tell him that they have same parents (father and mother). On further inquiry, it turns out that they both share the same date for their birthday.

"Are you twins," ask the headmaster.
"No," replies the boys.

Is it possible?

Peter wakes up daily to pick up his cycle and crosses the border between Spain and France daily with a bag on his shoulder. He is investigated daily by the officials but they don't find anything suspicious.

If we tell you that he is smuggling something what would it be?

No one wants to have it, but if one got it, he does not want to lose it. What is It?

How can you make the following equation true by drawing only one straight line: 5+5+5=550 ?

I noticed one of the words in the oxford dictionary is spelled incorrectly. What about you?

A boy and a girl are sitting on the porch.
"I'm a boy," says the child with black hair.
"I'm a girl," says the child with red hair.
If at least one of them is lying, who is which?