A rhombus has 4 angles. Two obtuse that are equal and two acute that are equal. If all of the angles in a rhombus add up to 360°, then one acute and one obtuse must add up to half that: 180°.
The acute to obtuse angle ratio is 1:3. Think of this as four parts. One part acute, three parts obtuse.
180 ÷ 4 = 45
Therefore, The acute angle is 45°, and the obtuse angle is 135°
