An express train takes 3 seconds to enter the tunnel which is 1 km long.
If it is travelling at 120 km an hour, how long will it take to pass completely through the tunnel?

Find the hidden tiger in the given optical illusion ?

Complete the series by replacing "?" with the correct number.

ST ND RD TH '?'

Find the Next Number in the Sequence

2 9 3 1 8 4 3 6 5 7 ?

Cristina was born in 1888. She just had her 30th birthday today how did that happen?

The ages of a father and son add up to 66.
The father's age is the son's age reversed.
How old could they be?
(3 possible solutions).

There is a box in which distinct numbered balls have been kept. You have to pick two balls randomly from the lot.

If someone is offering you a 2 to 1 odds that the numbers will be relatively prime, for example
If the balls you picked had the numbers 6 and 13, you lose $1.
If the balls you picked had the numbers 5 and 25, you win $2.

Will you accept that bet?

We have shown you a regular water barrel as below. Without using any measuring device can you check if the barrel is more than half-filled or less than half-filled?

What is the largest amount of money that you can possess in change and still if someone asks you for a dollar, you won't be able to give?

I have holes on the top and bottom. I have holes on my left and on my right. And I have holes in the middle, yet I still hold water. What am I?