In a triangle, the measure of the first angle is twice the measure of the second angle. the measure of the third angle 100 degrees more than the measure of the second angle

The measure of the angles in order are: 40, 20, 120 degrees 
Not exactly sure what the question was but I hope that answers it 

Working out: 

Let the measure of the second angle equal α
The first angle is double the second angle ie. 2α
The third angle is 100 more than the second angle ie. α+100 
We now have three angles: 2α, α, α+100

The angle sum of a triangle is always 180° 
∴2α + α + α+100 = 180 (group like terms) 
4α + 100 = 180 (-100)
4α = 80 (÷4)
α = 20