Find out a multi-digit number that if multiplied by the number 9 or any of its multiplications products (i.e. 18, 27, 36, 45,..) will result in the multiplication factor repeated (n) number of times.

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

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

I know a ten-letter word in the English language which can be typed using only the top rows of the computer keyboard.

Once upon a time, there was a castle on a square island. The entire island was surrounded by a 14m wide trench. The Romans had wanted to invade the castle and had brought a few wooden planks along with them to facilitate themselves in crossing the moat. The planks were however found to be only 13m long.

The Romans still managed to cross the trench. How did they do it?

There is a place where if I stand up straight, I will still be considered sideways.

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

There were three women in all the swimming costumes!
One was happy and the other two were sad!
The happy one was crying and the sad ones were smiling.
Why was this?

There are people and strange monkeys on this island, and you can not tell who is who (Edit: until you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.

There are five vowels (a, e, i, o, u) in the English language.
Can you tell us a word that contains all these vowels?

When we see 2 but call 10?