The Geometry of Circles Can you pass the

The Geometry of Circles Can you pass the test? Use a paper and pencil or calculator to answer these questions.

FORMULAS • Remember these formulas when you answer • • the questions. Diameter = 2 X Radius Circumference = 3. 14 X Diameter = Circumference divided by 3. 14 Area = Radius X 3. 14

Radius/Diameter • Mom bought a coffee can with a radius of 3 in. Will it fit on a shelf that is 6 in. wide so that the cupboard door will still close?

AREA • We own a restaurant. We bought new trays with an area of 300 sq. cm. each. If we buy bowls that have a diameter of 19 cm. each, will they fit on the trays?

Circumference • Will our basketball fit through our hoop? The ball has a circumference of 27 in. The hoop has a diameter of 9 in.

AREA • We had a yard sale and a man wanted to buy the trampoline if the area was over 700 sq. in. If the diameter is 30 in. , will he buy it?

Circumference • We need a paper plate big enough to hold a 22 in. circumference chocolate chip cookie. If the plate has a diameter of 7 in. , will it fit?

AREA • We have a CD with a radius of 6 cm. Can you figure out what its area is?

Circumference • We want to know the distance around the barrel lid to help us keep our horse’s circle tight going around the barrel when we race. If the lid’s diameter is 23 in. , what is the circumference?

AREA • Spongebob needed to know how much food he could fit on his plate without overflowing. If we figure the area using a diameter of 10 in. , what is the answer?

ANSWERS • • 1. Yes, it has a diameter of 6 in. 2. Yes, it has an area of 283. 385 sq. cm. 3. Yes, it has a diameter of 8. 59… in. 4. Yes, it has an area of 706. 5 sq. in. 5. No, it has a diameter of 7. 00636… in. 6. The area is 113. 04 sq. cm. 7. The circumference is 72. 22 in. 8. The area is 78. 5 sq. in.