Question

Explain how the number of pieces in a whole relates to the size of each piece

Answer 1

As the number of pieces in a whole gets larger, the size of the pieces gets smaller. This is represented by the denominator in a fraction. As the denominator increases, the number of pieces the whole is divided into also increases so the size of the pieces is smaller.
1/2 > 1/3 > 1/4 > 1/5 etc...

Fractions get smaller as the denominator gets bigger.