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?

Below, you will find the mathematical proof that 10 equals 9.99999?. But is that possible or there is something wrong about it? Can you find the error?

x = 9.999999...
10x = 99.999999...
10x - x = 90
9x = 90
x = 10

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

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

I am a prime number.
The double of myself is equal to the square of me.

which number am I?

Can you find out the missing number?

? 4 5 3 5

9 5 7 10 3

It is raining today at 11:59 am. What is the probability of sunny weather after 72 hours?

Can you solve the photo plexer logic ?

A person was found dead on a big green land with no trees or buildings around. When the police arrived, they found a piece of rock lying next to him and the man was wearing clothes comprising of red, blue and yellow colours.

Can you tell who the person is and what was the cause of death?

I am the largest in my family of fifty.
The youngest of our family lives separately from the rest of the family and so do I.
I am regarded as harsh and tough.
I am so large, you cut me in two equal halves,
each half would still be larger than the second largest member of the family.
Who am I?