Magic Mirror

There is a mirror that if you tell it a lie you are sucked into the mirror but if you tell the truth you are given money. A brunette walks up to the mirror and says, "I think I am the tallest person in the world," and shazam she is sucked into the mirror.
A few minutes later a ginger haired person walks up to the mirror and says, "I think I am the fattest person in the world," and shazam she is sucked into the mirror.
The next day a blonde walks up to the mirror. She stares deep into it and says, "I think," and shazam...