What is the measure of angle 4 if angle 1 = 76 degrees, angle 2 = 27 degrees and angle 3 = 17 degrees

Step-by-step explanation:

∠1 + ∠2 + ∠3 + a = 360   {Sum of all angles of quadrilateral}

76 + 27 + 17 + a = 360

          120 + a = 360

                    a = 360 -120

a = 240°

a + ∠4 = 360    

240 + ∠4 = 360

∠4 = 360 - 240

∠4 = 120°