Can you replace the question mark with the correct number?

Two boys were admitted to a school. When the headmaster asks them about their parents, they tell him that they have same parents (father and mother). On further inquiry, it turns out that they both share the same date for their birthday.

"Are you twins," ask the headmaster.
"No," replies the boys.

Is it possible?

I am looking for a word that change both gender and number when i add the letter 'S'.

What Word am I Looking For ?

Can you decipher the following common phrase?

T M C
A U O
H S M
W T E

I look at you, you look at me, I raise my right, you raise your left. What am I?

This puzzle is for Harry Potter fans. Do you know why Tom Riddle is called Lord Voldemort?

In this image, you can see three almost identical Doraemon images. Can you spot the odd one out from them?

You need to complete the maze by entering from the entrance marked below in the figure near the yellow circle, bottom left and leaving from the exit point near the green circle, bottom middle.

Rule of Game: You can move only by exchanging green and yellow circles.

Your last good ping-pong ball fell into a narrow metal pipe embedded one foot deep in concrete.
How can you get it out undamaged, if all the tools you have are your tennis paddle, shoe laces, and plastic water bottle, which does not fit into the pipe?

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?