I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?

Which of the below owl is odd one out?

Can you write down eight eights so that they add up to one thousand?

If you drop me I’m sure to crack, but give me a smile and I’ll always smile back. What am I?

Why 1729 is a magic number? Answer Logically.

This is a famous paradox which has caused a great deal of argument and disbelief from many who cannot accept the correct answer. Four balls are placed in a hat. One is white, one is blue and the other two are red. The bag is shaken and someone draws two balls from the hat. He looks at the two balls and announces that at least one of them is red. What are the chances that the other ball he has drawn out is also red?

What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?

John drives to his office at 20km/hr. After reaching the office, he realizes that today is a holiday. He went back at an average speed of 30km/hr. Discounting the time spent in the stoppage what was the average speed of his journey?

You board a train. The train will have to enter a tunnel soon. You are claustrophobic. Which place is the best for you to sit?

An American nightclub called 'The Coconut Grove' had a terrible fire in which over 400 people died. A simple design flaw in the building led to a high death toll. Subsequently, regulations were changed to ensure that all public buildings throughout the country eliminated this one detail, which proved deadly. What was it?