10+10 and 11+11 can give you the same answer.

Explain how?

When is the top of a mountain similar to a savings account?

Can you find a pattern and the missing number in the series given below?

100, 155, 258,? , 584, 819.

There were two grandmothers and their two granddaughters.
There were two husbands and their two wives.
There were two fathers and their two daughters.
There were two mothers and their two sons.
There were two maidens and their two mothers.
There were two sisters and their two brothers.
Yet there are only six, who are buried here,
All are born legitimate and relationships clear.
How can this happen?

A Man gave one of his sons 10 cents and another son was given 15 cents. What time is it?
Hint: Figure out the relation between time and number, is not so easy..:)

I have a five and a three-gallon jar. Assuming there is an infinite supply of water, how can I measure one-gallon water?

A wooden log balances equally on the scales when weighed with three-quarters of a pound and three-quarters of a wooden log.

Can you calculate the weight of the entire wooden log?

I look at you, you look at me, I raise my right, you raise your left. What am I?

Who is generally closer to the kids, mom or dad?

(it's a funny riddle)

In the Chess Board picture below white army is arranged. You need to add a black army on the board such that no piece is under any threat.
Note: Army comprised of 1 king, 1 queen, 2 rooks, 2 bishops, 2 knights, and 8 pawns.