Area & Circumference of Circles

Calculate circle area & circumference! Master formulas for radius, diameter, and pi. Geometry practice for kids.

Whats the Relationships Between Radius Diameter? Match the Radius with it's corresponding Diameter! Radius = 4 Diameter = 8 Radius = 7 Diameter = 14 Radius = 9 Diameter = 18 Radius = 13 Diameter = 26 Radius = 17 Diameter = 34 Fill in the Blanks! 1) The radius is equal to half the diameter2) The diameter is equal to twice the radius.3) To calculate the Circumference with the radius, we would use C = 2𝝿r4) To calculate the Circumference with the diameter, we would use C = 𝝿d If the radius of a circle is equal to 8, what will the circumference be? Type your step by step process for solving for circumference. Tyrese is curious how many inches of crust his pizza has. He measures the radius of the pizza as 10 inches. How many inches of crust does he have? 20 31.4 62.8 314 Alex's dining room table is circular with a radius of 48 inches. If each chair requires at least 50 inches of space along the table's perimeter, how many chairs can Alex buy for his table? 4 chairs 5 chairs 6 chairs 7 chairs If the diameter of a circle is equal to 32, what will the circumference be? Type your step by step process for solving for circumference. Jaime is getting a round pool in her backyard!!! But her dad is making her mark the perimeter of the pool before they dig the hole. If the diameter of the pool is equal to 40 feet, what is the perimeter of the hole going to be? Type your step by step process for solving for circumference. Marcus is making a hula hoop for his little sister. She's younger than him so it can't be too big. He decides that at it's widest, it can be 36 inches across. Calculate the circumference of the hula hoop. 36 inches 56.52 inches 113.04 inches 226.08 inches If the radius of the circle is 9, what will the area of the circle be? Type your step by step process for solving for the Area. If the radius of the circle is 14, what will the area of the circle be? Type your step by step process for solving for the Area. If the diameter of the circle is 12, what will the area of the circle be? Type your step by step process for solving for the Area. Jaime and her round pool are back! If the diameter of the pool is equal to 40 feet, what is the area of the hole for her pool going to be? Type your step by step process for solving for circumference. If the diameter of the circle is 20, what will the area of the circle be? 31.4 314 62.8 1,256 Megan has a cookie that has a radius of 4 centimeters. What is the area? Type your step by step process for solving for the radius. Kelly's new glasses have circular frames. If one lenses has a diameter of 6 centimeters, what is the area of one?