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

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

Three brothers Jacob, John, and James live in Mexico City. The product of the ages of these brothers is 175. Jacob and John are twins. How old is James?

Transform the word THINK into BRAIN while changing only one letter at a time in a manner that each of the word in the process is a real word!!!

You need to move three matchsticks to form three squares. Can you do it?

When I go in I might cause pain. I cause you to spit and ask you not to swallow. I can fill your hole. What am I?

You are playing a game with your friend Jack. There are digits from 1 to 9. You both will take turn erasing one digit and adding it to your score. The first one to score 15 points will win the game.

Would you want to play first or second?

PS: The sum should be exactly 15.

How many points are there on the globe where, by walking one mile south, then one mile east and then one mile north, you would reach the place where you started?

What number when divided in half becomes zero?

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?