Ratio, SM-Bank 025 The ratio of the angles in a triangle is 1:2:5. Calculate the sizes of all three angles? (2 marks) Show Answers Only \(22.5^{\circ}, 45^{\circ} \text{ and}\ 112.5^{\circ}\) Show Worked Solution \(\text{Total parts}=1+2+5=8\ \text{and the angle sum of a triangle}=180^{\circ}\) \(\dfrac{1}{8}\times 180\) \(=22.5\) \(\dfrac{2}{8}\times 180\) \(=45\) \(\dfrac{5}{8}\times 180\) \(=112.5\) \(\therefore\ \text{The angles in the triangle are }22.5^{\circ}, 45^{\circ} \text{ and}\ 112.5^{\circ}\)