What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see? What is it?

There are three light switches outside a room. One of the switches is connected to a light bulb inside the room.
Each of the three switches can be either 'ON' or 'OFF'.

You are allowed to set each switch the way you want it and then enter the room(note: you can enter the room only once)

Your task is to then determine which switch controls the bulb?

I have branches, but no fruit, trunk or leaves. What am I?

John is 45 years older than his son Jacob. If you find similarities between their ages, both of their ages contain prime numbers as the digits. Also, John's age is the reverse of Jacob's age.

Can you find their ages?

How will you measure 15 minutes using two hourglasses of 7 minutes and 11 minutes respectively?

When it is alive we sing, when it is dead we clap our hands. What is it?

Which word does the below Plexor means ?

Find the next number in the series

12, 20, 40, 72, 116, 172 ?

There was a competition where the contestants had to hold something. At the end of the event, the winner was a person who had no hands or feet. What was it that the contestants had to hold?

There is a shop where written:
Buy 1 for $1
10 for $2
100 for $3
I needed 999 and still only paid $3. How could this be financially viable for the shop-keeper?