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?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

An equation has been laid down using a few matchsticks. However, as you can see, the equation is not correct. Can you correct the equation if you are allowed to add or remove 5 matchsticks?

How many sides does a circle have?

Can you find out who is the kidnapper in below Picture and why, Explain ?

What is red and smells like blue paint?

I don't get anymore wetter, no matter how much rain falls on me.

Living above a star, I do not burn
Eleven friends and they do not turn
I can just be visited in a sequence, not once or repeatedly
PQRS are my initials
Can you tell my name accurately?

A professor thinks of two consecutive numbers between 1 and 10.
'A' knows the 1st number and 'B' knows the second number

A: I do not know your number.
B: Nor do I know your number.
A: Now I know.

What are the four solutions for this?

The answer I give is yes, but what I mean is no. What was the question?