SAT Math: Surface Area of 3D Figures
15+ practice questions in Praczo
The concept, explained
- 1
Surface area is the total area of all the faces of a 3D object added together.
- 2
For a rectangular prism, the formula is 2lw + 2lh + 2wh.
- 3
For a cylinder, the formula is 2πr² (the two circular bases) + 2πrh (the rectangular wrap around the side).
- 4
If the SAT asks for the surface area of a cube, it's 6s² (since all 6 faces are squares with area s²).
- 5
Read carefully: sometimes they ask for the area including only the walls and floor, but excluding the ceiling (so subtract one face).
- ✗ Calculating volume instead of surface area.
- ✗ Forgetting to multiply the area of one face by the total number of identical faces.
SAT-style practice
What is the total surface area of a cube with a side length of 4?
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