ACT Math · Circles, arcs, and sectors
A central angle measures 88°. What is the measure of an inscribed angle that intercepts the same arc?
A central angle measures 88°. What is the measure of an inscribed angle that intercepts the same arc?
Answer and explanation
Answer: G: 44°
An inscribed angle is half of the central angle that intercepts the same arc. The central angle is , so the inscribed angle is , choice G. Choice H () is the central angle itself. Choice J () doubles the angle instead of halving it, which would apply if you were going from an inscribed angle to its central angle. Choice F () halves twice. A useful check is that the inscribed angle's vertex lies on the circle, so it sees the same arc from farther away and appears smaller than the central angle.
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