An angle is one-fifth of its supplement. The measure of the angle is 

 

Sum of suplementary angles is 180 degree take 1st angle : x take 2nd angle as it is one fifth of the first angle to be : 1/5 x Therefore , x + 1/5 x = 180 6/5 x = 180 6x = 900 X = 150 degree therefore , x=150 1/5 x = 1/5 × 150 = 30 The angle which is one fifth of the supplement is 30 degree