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?

A and B have a certain number of chocolates with them. If B gives one chocolate to A, they will have an equal number of chocolates. But if A gives one chocolate to B, then A will be left with half the number of chocolates that B has.

Can you find out the number of chocolates they have right now?

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?

How many triangles are there on the puzzle below?

What makes this number unique: 8,549,176,320?

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

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

Which Number is the odd one out?

A) 7145
B) 2716
C) 5321
D) 4135

There are are five things wrong with this sentence; only geniuses will be able to to spot all of the mitstakes

My thunder comes before the lightning; my lightning comes before clouds; my rain dries all the land it touches. What am I?