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

Explain how?

What's the best place to go shopping in the ocean?

You need to remove two matchsticks to make the below equation true. Can you do it ?

The host of a game show offers the guest a choice of three doors. Behind one is an expensive car, but behind the other two are goats.
After you have chosen one door, he reveals one of the other two doors behind which is a goat (he wouldn't reveal a car).

Now he gives you the chance to switch to the other unrevealed door or stay at your initial choice. You will then get what is behind that door.

You cannot hear the goats from behind the doors, or in any way know which door has the prize.

Should you stay, or switch, or doesn't it matter?

The Puzzle: A girl, a boy, and a dog start walking down a road.

They start at the same time, from the same point, in the same direction.

The boy walks at 5 km/h, the girl at 6 km/h.

The dog runs from boy to girl and back again with a constant speed of 10 km/h. The dog does not slow down on the turn.
How far does the dog travel in 1 hour?

When 99 is considered higher than 100?

Before Mount Everest was discovered, what was the highest mountain in the world?

John decided to give his bike 3 coats of paint. Which coat would go on the first?

Which is the rope you never skip with?

The more it dries, the wetter it becomes. Can you tell what it is?