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

If,

20 % 5 = 24

21 % 7 = 33

42 % 6 = 67

Then;

66 % 6 = ?

Before Mount Everest was discovered, what was the highest mountain in the world?

Why do Chinese men eat more rice than Japanese men do ?

Find the next number in the sequence

1, 2, 6, 21, 88, __?

Decode the below four famous ciphers:

8P of the SS
1M of the E
1S of the SS
60M in 1H

Queen Elizabeth organised a royal party.

To Avoid uninvited guest royal family set a password.
Jack (an uninvited person) plan to enter the party. He stand nearby the door.

First guest comes, the security person said 'twelve' and guest replied with six.
Second guest comes , the security person said 'six' and guest replied with 'three'.

Jack thought is enough and he walked to the entry point. The security person said 'eight' , Jack replied smilingly 'four'.
He was immediately thrown out of the party. why ?

There are nine dots in the picture that has been attached with this question. Can you join all the dots by drawing four straight lines without picking up your pen?

You have a roll of cloth 1km long. You have a machine which cuts this roll into pieces of 10-meter-long cloth.

How long would it take for the machine to cut the roll if each cut took 4 secs?

What does below chemistry rebus means?