Equal shares of identical wholes might be different shapes.

These squares are the same size.

Square A is divided into 4 equal parts.

So, the area of each part is $\frac{1}{4}$ of the area of square A.

Square B is divided into 4 equal parts.

So, the area of each part is $\frac{1}{4}$ of the area of square B.

Square A and square B are the same size, which means they have the same area.

So, the area of $\frac{1}{4}$ of square A is equal to the area of $\frac{1}{4}$ of square B.