What is so fragile that saying its name breaks it?

What does this Rebus Picture mean?

In a competitive exam, each correct answer could win you 10 points and each wrong answer could lose you 5 points. You sat in the exam and answered all the 20 questions, which were given in the exam.
When you checked the result, you scored 125 marks on the test.

Can you calculate how many answers given by you were wrong?

Replace each alphabet with the number (1-9) to make the below equation correct.

AB * C = DE - F = GH / I

A sundial has the fewest moving parts of any timepiece. Which has the most?

What is red and smells like blue paint?

A wooden log balances equally on the scales when weighed with three-quarters of a pound and three-quarters of a wooden log.

Can you calculate the weight of the entire wooden log?

When can we add 2 to 11 and get 1 as the correct answer?

In the figure, you can see nine stars. What you have to do is connect all of them by using just four line and without lifting your hand i.e. in a continuous flow.

A man dies of old age on his 25 birthday. How is this possible?