Area of a circle, and of parts of a circle
Grade 7 Math Worksheet - Building Confidence
Circle the best answer, or write your answer on the line.
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Grid, each square 0.5 cm by 0.5 cm. The wedges laid point up, point down make a near-rectangle 7.85 cm wide (half the distance around the circle) and 2.5 cm tall (the radius).
Ari cuts a round cookie into equal wedges and lays them point up, point down into a near-rectangle. The wedges are very well behaved. What is the area of the cookie in square cm?
Bo cuts a round pizza into equal wedges and lays them point up, point down into a near-rectangle. The slices lined up like a team. What is the area of the pizza in square cm?
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Grid, each square 2.5 cm by 2.5 cm. The wedges laid point up, point down make a near-rectangle 36.11 cm wide (half the distance around the circle) and 11.5 cm tall (the radius).
Esme cuts a round paper plate into equal wedges and lays them point up, point down into a near-rectangle. The scissors went round. What is the area of the paper plate in square cm?
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Grid, each square 3 cm by 3 cm. The wedges laid point up, point down make a near-rectangle 47.1 cm wide (half the distance around the circle) and 15 cm tall (the radius).
Jun cuts a round pizza into equal wedges and lays them point up, point down into a near-rectangle. It turned into a very tidy rectangle. What is the area of the pizza in square cm?
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Grid, each square 1 cm by 1 cm. The wedges laid point up, point down make a near-rectangle 10.99 cm wide (half the distance around the circle) and 3.5 cm tall (the radius).
Kira cuts a round cookie into equal wedges and lays them point up, point down into a near-rectangle. The chips stayed in their wedges. What is the area of the cookie in square cm?
Luz's button is 3 cm across, so its radius is 1.5 cm. It has four holes. What is its area in square cm?
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Grid, each square 1 cm by 1 cm. A circle with its diameter 9 cm drawn across and its radius 4.5 cm drawn from the middle to the edge. Below it, the wedges laid out as a rectangle 4.5 cm tall and 3.14 radii wide.
Milo's hand mirror is 9 cm across, so its radius is 4.5 cm. It checks for smudges. What is its area in square cm?
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Grid, each square 3 cm by 3 cm. A circle with its diameter 21 cm drawn across and its radius 10.5 cm drawn from the middle to the edge. Below it, the wedges laid out as a rectangle 10.5 cm tall and 3.14 radii wide.
Noah's clock face is 21 cm across, so its radius is 10.5 cm. It is always on time. What is its area in square cm?
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Grid, each square 1 cm by 1 cm. A circle with its radius 5.5 cm drawn from the middle to the edge; the distance around it is 34.54 cm. Below it, the wedges laid out as a rectangle one radius tall and half the circumference wide.
Tala's hand mirror has a radius of 5.5 cm and a circumference of 34.54 cm. It likes what it sees. What is its area in square cm?
Zee's plate has a radius of 10 cm and a circumference of 62.8 cm. It would like to be a frisbee. What is its area in square cm?