To find surface area, find the area of all the shapes and add it all together. This shape has 4 triangle faces. They are all the same. So we can find one of them and times by 4.
Area of a triangle:
A = 1/2b•h
= 1/2• 5 • 8
= 1/2 • 40
= 20
One triangle has area 20, so times by 4 (bc four triangles)
people owned a bike and 
did not. 
x=72
x=72
x=24