A triangle has two of its angles in the ratio of l : 2. If the measure of one of its angles is 30 degrees. what is the measure of the largest angle of the triangle in degrees ?

Explanation:

If the angle be 30∘, then according to ratio,

Second angle = 60∘

Third angle = 180∘ – 60∘ – 30∘ = 90∘

If the given ratio be of two other angles, then

x + 2x = 180∘ – 30∘ = 150∘

=> 3x = 150∘ => x = 50∘

∴ Second angle = 2 × 50 = 100∘

Hence, the largest angle

= 90∘ or 100∘