Geometryhard · Past Paper
In a cyclic quadrilateral, if the ratio of three consecutive angles is 1:2:3, find the fourth angle.
A60 degrees
B90 degrees
C120 degrees
D180 degrees
✓ Correct Answer: B — 90 degrees
Let angles be x, 2x, 3x. x + 3x = 180 (opp angles) => 4x = 180, x = 45. 2x + 4th = 180 => 90 + 4th = 180 => 4th = 90.
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