(i)

Total people at the rally = 240 + 200 + 160 + 120

Total people at the rally = 720

Angle of sector = $\frac{\mathrm{Number}}{\mathrm{Total}}$ x 360^o

Angle of sectors

Note: 360 divides itself once and 720, 2 times.

The sum of all the angle of sectors should be 360^o.

(ii)

Percentage = $\frac{\mathrm{Number}}{\mathrm{Total}}$ x 100%

Method I

Number of females at the rally = Women + Girls
Number of females at the rally = 240 + 120
Number of females at the rally = 360

Total people at the rally = 720

Percentage (females) = $\frac{360}{720}$ x 100% = 50%

Note: 360 divides itself once and 720, 2 times. 2 divides itself once and 100, 50 times.

Method II

Using the angle of sectors

Total angle of sectors for females = Angle of sector for women + Angle of sector for girls
Total angle of sectors = 120 + 60 = 180

Total angle of sectors for the people at the rally is 360

Percentage (females) = $\frac{180}{360}$ x 100% = 50%

Note: 180 divides itself once and 360, 2 times. 2 divides itself once and 100, 50 times.