Optical Illusion Eye Test: You Have A Brain Like Computers If You Can Spot Two B's Among R's In 8 Seconds!

What is black when you buy it, red when you use it, and gray when you throw it away?

Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?

John’s parents have three sons: Snap, Crackle, and what’s the name of the third son?

Why are all black people so quick ?

using four eights (8) and a one (1) and one mathematical symbol , create the number 100

What does the below mathematical rebus mean?

The host of a game show, offers the guest a choice of three doors. Behind one is a 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?

A Man gave one of his sons 10 cents and another son was given 15 cents. What time is it?
Hint: Figure out the relation between time and number, is not so easy..:)

In the Mexico City area, there are two Houses H1 and H2. Both H1 and H2 have two children each.
In House H1, The boy plays for Mexico Youth academy and the other child plays baseball.
In House H2, The boy Plays soccer for his school in Mexico and they recently have a newborn.

Can you prove that the probability of House-H1 having a girl child is more than that of House-H2?