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

Explain how?

How many letters are in the alphabet?

First, think of the colour of clouds. Next think the colour of snow. Last, think of the colour of the moon. Now, what do cows drink?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

John’s parents have three sons: Snap, Crackle, and what’s the name of the third son?

Can you count the number of rectangles on a chessboard?

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

Too much grey makes things difficult. However, your task here is to find the elephant hidden in the picture.

It can't be seen, can't be felt, can't be heard, and can't be smelt.
It lies behind stars and under hills, And empty holes it fills.
It comes first and follows after, Ends life, and kills laughter.
What is it?

If two fifty-foot ropes are suspended from a forty-foot ceiling that is twenty feet apart, how much rope will you be able to steal if you have a knife?