The angles of a triangle are in the ratio 3 to 4 to 5 What is the measure of the smallest angle?

Since the sum of the measures of the angles of a triangle is 180 degrees, then:

3x + 4x + 5x = 180

12x = 180

x = 15

3x = 3 x 15 = 45

4x = 4 x 15 = 60

5x = 5 x 15 = 75

Thus the angles of the triangle are 45, 60, and 75 degrees.