- A120°
- B110°
- C130°
- D100°
Step-by-Step Solution
Angle sum of a quadrilateral is 360°. Fourth angle = 360 − (90 + 85 + 65) = 360 − 240 = 120°.
Answer: A) 120°
Three angles of a quadrilateral are 90°, 85° and 65°. What is the fourth angle?
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