Try some yourself
Question 1
Calculate all the angles at the centres of these objects.

Answer
(a) Each of the four angles is 360° ÷ 4 = 90°.
(b) The two upper angles are both 180° ÷ 2 = 90°, and the lower angle is 180°.
(c) Each of the six angles is 360° ÷ 6 = 60°.
(d) Each of the twenty angles is 360° ÷ 20 = 18°.
(e) The acute angle between the hands is 360° ÷ 12 = 30°; the reflex angle is 360° − 30° = 330°.
(f) Each of the three angles is 360° ÷ 3 = 120°.
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