What does this simple rebus mean?

Solve the counting riddle by identifying the number of triangles in the given picture.

John is selling fruits.
He sells grapes at $30, Dates $25, and a Wolfberry $45.
At what price does he sell fig?

PS: Logical Thinking

A woman lives in a skyscraper thirty-six floors high and is served by several elevators which stop at each floor going up and down. Each morning she leaves her apartment and goes to one of the elevators. Whichever one she takes is three times more likely to be going up than down. Why?

How old is your son? asked a man to his neighbour. My son is five times as old as my daughter and my wife is five times as old as my son. I am twice as old as my wife whereas my grandmother, who is celebrating her eighty-first birthday is as old as all of us put together.

How old is the man's son ?

What number comes next in this sequence:
7 8 5 5 3 4 4 _

This is a classy optical illusion puzzle. What more you can find except bricks in the image below?

What Deficiency does the below rebus represent?

VIT_MIN

2, 3, 5, 9, 17, _ What is the next number in the sequence?

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.