the number on the bottom of the fraction (denominator) is equal to the total number of possibilities (in this case there are 6 possibilities). for the number on top (the numerator) we are trying to work out the probability of rolling a 3. a 3 is only 1 of the 6 options (1, 2, <u>3</u>, 4, 5, 6) so the number on top is 1.
