Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?

If,

6 / 7 = 2
3 / 9 = 7
8 / 2 = 6

Then

4 / 5 = ?

What is full of holes but still holds water?

What is represented by this rebus?

once
time

I am lying and I always lie. Tell me whether I am lying or telling the truth.

A rubber ball keeps on bouncing back to 2/3 of the height from which it is dropped. Can you calculate the fraction of its original height that the ball will bounce after it is dropped and it has bounced four times without any hindrance ?

A man says, "Brothers and sisters, have I none, but that man's father is my father's son." Who is that man?

By adding four matchsticks, can you divide the square shown in the picture into two equal parts?

What makes this number unique: 8,549,176,320?

What 8 letter word can have a letter taken away and it still makes a word. Take another letter away and it still makes a word. Keep on doing that until you have one letter left. What is the word?