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Two angles of a quadrilateral are 68° and 76°. If the other two angles are in the ratio 5 : 7; find the measure of each of them.

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#### Solution

Two angles are 68° and 76°

Let other two angles be 5x and 7x

68° + 76°+ 5x + 7x = 360°

12x + 144° = 360°

12x = 360° – 144°

12x = 216°

x = 18°

angles are 5x and 7x

i.e. 5 x 18° and 7 x 18° i.e. 90° and 126°

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