What happened when the wheel was invented?

Can you find the missing piece of the Porsche?

If you’ve got me, you want to share me; if you share me, you haven’t kept me. What am I?

Can you solve the below tricky visual equation?

If your uncle’s sister is not your aunt, what relation is she to you?

Before reading ahead, you must know the fact that only one of the people here is telling the truth.

A says that B is lying.
B says that C is lying.
C says both A and B are lying.

Can you find out who is speaking the truth?

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

What's the only room from which no one can enter or leave

The centre of the third figure is empty. What digit should fit inside?

A mathematics teacher took exams for his students. Out of the total students, 25% passed both the tests included in the exam. However, only 42% were able to clear the first test.

Can you find out the percentage of those students who passed the first test and also passed the second test?