Why is 6 afraid of 7?

What is always in front of you but can’t be seen?

A boy and a girl are sitting on the porch.
"I'm a boy," says the child with black hair.
"I'm a girl," says the child with red hair.
If at least one of them is lying, who is which?

What is so fragile that saying its name breaks it?

In the given figure, move three matchsticks so that the resulting figure contains two rectangles.

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

Complete the series by replacing "?" with the correct number.

ST ND RD TH '?'

I went to the bookshop and spent one-half of the money that was in my purse.

When I came out, I found that I had as many cents as I had dollars and half as many dollars as I had cents when I went in. Find the money in my purse when I entered the store.

Out of four images which one is the odd one out?

I have branches, but no fruit, trunk or leaves. What am I?