A mother is 21 years older than her child. In exactly 6 years from now, the mother will be exactly 5 times as old as the child.
Where's the father?

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

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

A clock loses 10 minutes each hour. If the clock is set correctly at noon, what time is it when it reads 3 PM?

It spends most of its day eating white, but when it’s quick enough, it gets to eat fruit and sometimes some blue things. It’s in a dark room, where the walls are blue, it runs from a ghost that roams the halls and haunts it all the time. What is it?

A time long back, there lived a king who ruled the great kingdom of Trojan House. As a part of the renovation of the kingdom to meet future security needs, he asked his chief architect to lay down a new play in a manner that all of his 10 castles are connected through five straight walls and each wall must connect four castles together. He also asked the architect that at least one of his castles should be protected with walls. The architect could not come up with any solution that served all of King's choices, but he suggested the best plan that you can see in the picture below. Can you find a better solution to serve the king's demand?

Spot what is wrong here in below Picture?

There are forty elephants and they have forty-fore heads. How can this be possible?