Finding Area and Circumference of a Circle. Draw a picture: 6 m Choose formula: A = πr 2 Substitute and solve: A = 3.14(6) 2 A = 113 m 2 Patricia buys.

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Finding Area and Circumference of a Circle

Draw a picture: 6 m Choose formula: A = πr 2 Substitute and solve: A = 3.14(6) 2 A = 113 m 2 Patricia buys a round dinner table. The radius of dinner table is 6 meters. What is the area of table?

Steven purchases a bowl. The diameter of the bowl is 14 cm. What is the circumference of the bowl? Finding Area and Circumference of a Circle Draw a picture: 14 cm Choose formula: C = πd Substitute and solve: C = 3.14(14) C = 44 cm

Finding Area and Circumference of a Circle Draw a picture: 5 in Choose formula: C = 2 πr Substitute and solve: C = 2(3.14)(5) C = 31.4 in Daniel wants to buy cookies for his friend. The radius of a cookie is 5 inches. What is the cookie’s circumference?

Finding Area and Circumference of a Circle Draw a picture: 8 cm Choose formula: A = πr 2 Substitute and solve: A = (3.14)(4) 2 A = cm 2 Donna makes a round pizza. She wants to put a cheese layer on the pizza. If the cake is 8 cm in diameter, how many square cm of cheese layer does she need to put on the pizza? We know diameter, but need radius Radius is one half the diameter, so r = 4 cm

Finding Area and Circumference of a Circle Draw a picture: Choose formula: A = πr 2 Substitute and solve: A =(3.14)(6) 2 – (3.14)(2) 2 What are we looking for? Area of the carpet remaining (blue) 12 m 4 m Subtract the small circle from the big circle A(carpet) – A(table) A = 113 – 13 = 100 m 2 Charles has a circular carpet in his drawing room. He wants to put a circular table in middle of the carpet. The diameter of the carpet is 12 meters and the diameter of the table is 4 meters. Calculate how much area of carpet is left after putting the table in place? We know d but we need r

Finding Area and Circumference of a Circle Draw a picture: Choose formula: A = πr 2 Substitute and solve: A =(3.14)(5) 2 – (3.14)(0.5) 2 What are we looking for? Area of the bottom of fountain (blue) 10 m 1 m Subtract the small circle from the big circle A(fountain) – A(statue) A =78.5 – 0.79= m 2 A circular fountain has a diameter of 10 meters. The statue in the middle has a diameter of 1 meter. What is the area of the bottom of the fountain? We know d but we need r