Shade the region in the following diagrams based on the given fraction.

Total participants = 225
Female participants = 144
Male participants = Total participants - Female participants

$$\text{Male participants} = 225 - 144 = 81$$

Since the number of seats in each column and row is the same, the total number of seats in the female section (144) must be a perfect square. The number of seats in a row is the square root of the total seats.

$$\text{Seats in a row (female)} = \sqrt{144} = 12$$

Similarly, the total number of seats in the male section (81) must be a perfect square. The number of seats in a row is the square root of the total seats.

$$\text{Seats in a row (male)} = \sqrt{81} = 9$$

The number of seats in a row in the male's section is $\boxed{9}$ and in the female's section is $\boxed{12}$.

a) Shade the region in the following diagrams based on the given fraction.

(i) Fraction: $\frac{1}{4}$. Diagram: An octagon divided into 8 equal triangular sections.
To represent $\frac{1}{4}$ of 8 sections, we calculate:

$$\frac{1}{4} \times 8 = 2$$

You should shade 2 of the 8 triangular sections.

(ii) Fraction: $\frac{3}{5}$. Diagram: A grid of 20 small squares.
To represent $\frac{3}{5}$ of 20 squares, we calculate:

$$\frac{3}{5} \times 20 = 3 \times 4 = 12$$

You should shade 12 of the 20 small squares.

(iii) Fraction: $\frac{2}{3}$. Diagram: Three circles, each divided by an 'X'.
This fraction refers to the proportion of the total circles. To represent $\frac{2}{3}$ of 3 circles, we calculate:

$$\frac{2}{3} \times 3 = 2$$

You should shade 2 of the 3 circles completely.