This is a classy optical illusion puzzle. What more you can find except bricks in the image below?

Can you find out the missing number?

? 4 5 3 5

9 5 7 10 3

After teaching his class all about Roman numerals (X = 10, IX=9 and so on) the teacher asked his class to draw a single continuous line and turn IX into 6. The teacher's only stipulation was that the pen could not be lifted from the paper until the line was complete.

One day, I thought of ways that can be used for creating a palindrome. So I decided that I will turn into a larger number by adding the reversed digits to the original number and keep doing it till I finally obtained a palindrome.

I am not sure if this process will always result in a palindrome eventually but I was able to produce a four-digit palindrome. Can you guess my starting number?

What occurs twice in a week, once in a year but never in a day?

If nine thousand, nine hundred nine dollars is written as $9,909,
how should twelve thousand, twelve hundred twelve dollars be written?

There is a barrel with no lid and some wine in it. 'This barrel of wine is more than half full,' said Curly. 'No it's not,' says Mo. 'It's less than half full.' Without any measuring implements and without removing any wine from the barrel, how can they easily determine who is correct?

I make a loud sound when I’m changing. When I do change, I get bigger but weigh less. What am I?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

What does the following represent?

N N N N N N N

A A A A A A A

C C C C C C C