A pie chart shows the hobbies of 180 pupils. Reading is 120°, Sports is 90°, Music is 60°. Calculate the number of pupils for each hobby and the percentage for Reading.

Total number of pupils = 180.
The angles for each hobby are:

• Reading: $120^\circ$
• Sports: $90^\circ$
• Music: $60^\circ$ The angle for Art is not explicitly given, so we calculate it: Angle for Art = $360^\circ - (120^\circ + 90^\circ + 60^\circ) = 360^\circ - 270^\circ = 90^\circ$.

The number of pupils for a hobby is calculated as $\frac{\text{Angle for hobby}}{360^\circ} \times \text{Total number of pupils}$.

a)

i) Reading:
Number of pupils = $\frac{120^\circ}{360^\circ} \times 180 = \frac{1}{3} \times 180 = \boxed{\text{60 pupils}}$

ii) Sports:
Number of pupils = $\frac{90^\circ}{360^\circ} \times 180 = \frac{1}{4} \times 180 = \boxed{\text{45 pupils}}$

iii) Music:
Number of pupils = $\frac{60^\circ}{360^\circ} \times 180 = \frac{1}{6} \times 180 = \boxed{\text{30 pupils}}$

iv) Art:
Number of pupils = $\frac{90^\circ}{360^\circ} \times 180 = \frac{1}{4} \times 180 = \boxed{\text{45 pupils}}$

The percentage for a hobby is calculated as $\frac{\text{Angle for hobby}}{360^\circ} \times 100\%$.

b)

i) Reading:
Percentage = $\frac{120^\circ}{360^\circ} \times 100\% = \frac{1}{3} \times 100\% = \boxed{33.33\%}$ (rounded to two decimal places)

ii) Sports:
Percentage = $\frac{90^\circ}{360^\circ} \times 100\% = \frac{1}{4} \times 100\% = \boxed{25\%}$

iii) Music:
Percentage = $\frac{60^\circ}{360^\circ} \times 100\% = \frac{1}{6} \times 100\% = \boxed{16.67\%}$ (rounded to two decimal places)

iv) Art:
Percentage = $\frac{90^\circ}{360^\circ} \times 100\% = \frac{1}{4} \times 100\% = \boxed{25\%}$