How many sides does a circle have?

Can you make numbers like 24, using numbers 3,3,7 & 7 with any arithmetic operator?

A tree doubled in height each year until it reached its maximum height over the course of ten years. How many years did it take for the tree to reach half its maximum height?

I am a type of word that is spelt incorrectly or used differently, on purpose for humour. What am I?
Hint 1: You can find me in a joke.
Hint 2: I am a play on words.

Find the Odd One Out?
84129
32418
47632
36119
67626
72927

John left on a horse on Thursday , was gone for two days, and came back on Thursday after completing his work. How did that happen?

Which is the smallest number that you can write using all the vowels exactly once?

In the image below, you can see two glasses and two matchsticks.You need to move four matchsticks in such a manner that the crosses come inside the glasses. Note: you cannot move the crossed.

A pack of cards has 40 cards. You are blindfolded. Out of 40, 25 cards are facing down while 15 are facing up. You have been asked to divide this pack of cards into two decks - so that each deck contains an equal number of face-up cards. Remember, you are blindfolded.

How will you do it?

If it took eight men ten hours to build a wall, how long would it take four men to build it?