Video narration
What do these two numbers, three over four, really mean? Imagine one whole pizza, divided into four equal slices. Each slice is the same size, because fractions describe equal parts of a whole. The bottom number tells how many equal parts make the whole. This is the denominator. Now count the slices being chosen. If three slices are counted, the top number is three. It is the numerator: the number of equal parts we are counting. So the two numbers stop being separate. Three over four means three equal parts out of four equal parts in one whole pizza. That is why the slices must be equal. If one piece were bigger, the parts would not be equal, so the fraction would not work. So, what does three over four mean? It means three equal pizza slices out of four equal slices in the whole pizza.