Circles

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. Source: Robert Kaplinsky

Directions: Using the digits 0 to 9 at most one time each, place a digit in each box two times: once where the central angle is greater than 130° and once where it is less than 130°. You may reuse all the digits each time. Source: Robert Kaplinsky

Directions: Using the digits 0 to 9 at most one time each, place a digit in each box so that the radius and angle measure result in the sector area is as close to 60 units2 as possible. Source: Robert Kaplinsky

Directions: Using the digits 0 to 9 at most one time each, place a digit in each box so that the radius and angle measure result in the sector area. Source: Robert Kaplinsky

Directions: What is the longest chord in a circle that has an area of 25π square units? Source: Nanette Johnson

Directions: What is the area of the smallest square that could fit around (circumscribed about) a circle with area 100π square units? Source: Nanette Johnson

Directions: What is the biggest area of a quadrilateral you can fit in a circle that has a circumference of 20π units? Source: Nanette Johnson