GIVEN :Cyclic QUADRILATERAL = WXYZThe MEASURE of angle Z is 10 more than twice the average of the measures of other three anglesThe measure of angle Z = ?Calculation :A quadrilateral will have 4 angles totaling 360 degrees.w + X + y + z =360We also know that z is 10 more than twice the average of the other 3 angles. z = 2 × (w + x + y)/3 +10w + x + y + 2 × (w + x + y)/3 +10 =3605/3 × (w + x + y) + 10 = 360 5/3 × (w + x + y) = 350 w + x + y = 210z = 360 - 210 = 150 ∴ The measure of angle z is 150