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?

There are three identical triplets sisters. Demi is the oldest of them all and she always speaks the truth. Diana is the next one who is a liar always. Drew, the youngest of them all speaks both truth and lies randomly.

On a rainy day, a family friend Victor visited them. Since there were starkly identical, he was not able to recognize them. Thus to clarify, he asked one question to each one of them.

He started with the one standing on the left and asked, 'Which sister is in the middle of you three?' She answered, 'That's Demi.'

Then, he asked the one standing in the middle, 'What is your name?' She answered, 'I am Drew.'

Finally, he asked the one standing on the right, 'Who is standing in the middle?' She answered, 'She is Diana.'

Victor was left baffled. He asked the questions three times and received different answers every time.

Can you tell who was who?

Can you find a number that lies one third of the distance between 1/3 and 2/3?

Solve the following series:
AZ, GT, MN, __, YB

Find the next number in the series below

21 32 54 87 131 ?

Only one colour, but not one size,
Stuck at the bottom, yet easily flies.
Present in sun, but not in rain,
Doing no harm, and feeling no pain.
What is it?

Why is the Hole below a Lock?

A chess tournament is taking place on knock-out terms (the one who loses the match is out of the game).
(a) If 10 matches are played in total, how many players participated?
(b) If 20 players took part in the tournament, how many matches were played?

By removing one matchstick and adding one matchstick, can you convert the word "ZOO" to an animal name?

What does this mathematical rebus means ?