You can see three almost identical images below. Can you spot the odd one out from them?

If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

You are presented with three boxes. One of them has a red ball inside and the other two have a black ball inside each of them. You are asked to pick up the one with red ball and you pick one. Now, one of the other boxes is opened and it is found to have a black ball.

You are presented with a chance to change your box with the one that is left closed. Will you change your box? Why or why not?

The more of this there is, the less you see. What is it?

If an electric train is travelling south, then which way is the smoke going?

A rubber ball keeps on bouncing back to 2/3 of the height from which it is dropped. Can you calculate the fraction of its original height that the ball will bounce after it is dropped and it has bounced four times without any hindrance ?

John and Jenni are a married couple. They have two kids, one of them is a girl. Assume safely that the probability of each gender is 1/2.
What is the probability that the other kid is also a girl?

Hint: It is not 1/2 as you would first think.

John replied, when asked how old he was. In 2 years he will be twice as old as he was five years ago.' How old is he ?

What's a single-digit number with no value?

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