SAT · Additional Topics in Math · Circles, arcs, and sectors
Question sat-q-00185
Medium Multiple choice No calculator
The question
A circle has radius 8. What is its area, in terms of π?
- 64π
- 128π
- 8π
- 16π
Show answer & worked solution
Answer: 64π
Worked solution. Area of a circle is πr². Here r = 8, so area = π × 8² = 64π.
Why each wrong choice is wrong. Confusing area (πr²) with circumference (2πr) is the dominant error here. The 2πr distractor catches it perfectly.
Test-day tactic. Area scales as the square of the radius; circumference scales linearly. When in doubt, sketch a unit circle and check.
About this question type
Items test the standard circle equation (x − h)² + (y − k)² = r², arc length and sector area as fractions of the full circle, inscribed and central angles, and tangent-chord relationships.
You will see a question shaped like this one on roughly every other official SAT form, typically at a moderate position in the section — solidly within the range that separates a 600-band student from a 700-band student. Treat any miss in this subtopic as a signal to drill the subtopic page before you do another full practice test.