There are 13 hearts in a deck of 52 cards. So the probability of drawing a heart is 13/52 or 1/4. To find out what the chances of all three being hearts, we can multiply this probability:
[tex]\sf\dfrac{13}{52}\times\dfrac{12}{51}\times\dfrac{11}{50}\rightarrow\boxed{\sf\dfrac{11}{850}}[/tex]
So the chances that all three cards will be hearts is 11/850.