Which flower has two lips?

Christina, Allison and Lena are 3 daughters of John a well-known Mathematician, When I asked John the age of their daughters. He replied "The current age of her daughters is prime. Also, the difference between their ages is also prime."

How old are the daughters?

A man is shown a portrait painting. He looks closely, then tells, “Brothers and sisters have I none, but that man’s father is my father’s son!” Who is the man in the portrait?

Two old friends, Jack and Jill, meet after a long time, and discussing as:

Jack: Hey, how are you, man?

Bill: Not bad, got married and I have three kids now.

Jack: That's awesome. How old are they?

Bill: The product of their ages is 72 and the sum of their ages is the same as your birth date.

Jack: Cool..But I still don't know.

Bill: My eldest kid just started taking piano lessons.

Jack: Oh, now I get it.

How old are Bill's kids?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

What does the following represent?

N N N N N N N

A A A A A A A

C C C C C C C

At my favorite fruit stand,
an orange costs 18,
a pineapple costs 27,
and a grape costs 15.
Using the same logic, can you tell how much a mango costs?

Irene killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

You can take four of the five letters out of this word, but the pronunciation never changes. What is the word?

John replied, when asked how old he was. In 2 years he will be twice as old as he was five years ago.' How old is he ?