Open Middle®
Directions: Using the digits 0 to 9, at most one time each, place a digit in each box so that the central angle has the greatest possible value.
Hint
How can we figure out which central angles are or are not worth checking?
Answer
The greatest possible central angle value comes from:
Central angle: 156°
Inscribed angle: 78°
Circumscribed angle: 24°
Central angle: 156°
Inscribed angle: 78°
Circumscribed angle: 24°
Source: Robert Kaplinsky