Hi,
The second angle is twice the measure of the first angle.
The third angle is 3 times the measure of the second angle.
Let x , 2x and 6x represent the measure of the 1st, 2nd and 3rd angle respectively
Question states***sum of the measures of the angles of a triangle is 180 degrees
x + 2x + 6x = 180°
9x = 180°
x = 20°
Measures of the angles are: 20°, 40° , 120°