If one base of a trapizoid is 7.2 inches and the other base is 6.4 and the hieght is 3.6 what is it all around

If the base is 7.2 and the top is 6.4, you know that the extra bit on the bottom is (7.2 - 6.4 = ) 0.8. This means on each side the base of the imaginary triangle is 0.4

Using Pythagoras' theorem, we know a² + b² = c²

0.4² + 3.6² = c²

c = √0.16 + 12.96

c = √13.12

c = 3.62 - > this is the diagonal length of one of the sides of the shape.

So the distance all around is 7.2 + 6.4 + 3.62 + 3.62 = 20.84 inches