Geometrymedium · Past Paper
An arc of length 15 cm subtends an angle of 45 degrees at the center. Find the radius.
A60/pi
B30/pi
C15/pi
D45/pi
✓ Correct Answer: A — 60/pi
Arc length = (theta/360) * 2 * pi * r. 15 = (45/360) * 2 * pi * r => 15 = (1/8) * 2 * pi * r => 15 = pi * r / 4 => r = 60 / pi.
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