Question

if three angles in a tringle are such that 2 angle is twice of first than third angle is average of first two

Answer 1

1st angle = x
2nd angle = 2x

third angle = 2x+x/3

(Average = Sum of given values divided by number of given values)
= 3x/3 = x
third angle = x

sum of all angles = 180° (angle sum Property of triangles)

x+2x+x = 180°
2x+2x = 180°
4x = 180°
x = 180/4
x = 90/2
x = 45°

therefore the first angle is 45°
the second angle is 2x = 2(45) = 90°
the third angle is x = 45°