Four of the angle measurements $62°,85°,99°,108°,114°$ are the measures of the angles in the same quadrilateral. Which angle measure is not?
Pick one
Solution
The sum of the four angle measurements in a quadrilateral is 360°.
The sum of the five angle measurements given is 62°+85°+99°+108°+114°=468°.
The difference, 468°−360°=108°, is the measure of the angle that is not in the quadrilateral.
(We may confirm that 62°+85°+99°+114°=360°.)
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