Let the smallest angle be x.
Then measure of second angle = 2x (Given measure of one angle is twice the smallest angle)
Measure of third angle = 3x.
(Given measure of other angle is thrice the smallest angle)
x+5x+3x=180∘ (Angle sum property of a triangle)
9x=180∘
x=1809=20∘
5x=2×20=100∘
3x=3×20=60∘
Hence the measures of the angles are 20∘,100∘ and 60∘.