Circles Pre Assessment

What is the radius of a circle that has a diameter of 26 in?

• 52 in

• 13 in

• 26 in

• 81.64 in

Answer explanation

The radius of a circle is half of its diameter. Therefore, the radius of a circle with a diameter of 26 in is 13 in. Hence, the correct answer is 13 in.

Tags

CCSS.7.G.B.4

What is the diameter of a circle that has a radius of 17 in?

• 17 in

• 8.5 in

• 34 in

• 53.38 in

Answer explanation

The diameter of a circle is twice the radius, so the diameter is 2 * 17 in = 34 in. Therefore, the correct answer is 34 in.

Tags

CCSS.7.G.B.4

How do you find the area of a circle?

• 2 • π • r

• π • d

• π • r²

• C ÷ d

Answer explanation

To find the area of a circle, you use the formula π • r^2, where r is the radius of the circle. This formula calculates the area enclosed by the circle.

Tags

CCSS.7.G.B.4

(Might need paper and pencil for this one!) What is the circumference of a circle whose radius is 5 cm? (Use 3.14 for pi)

• 31.4 cm

• 10 cm

• 25.6 cm

• 2.5 cm

Answer explanation

The circumference of a circle is calculated using the formula 2 * pi * radius. Substituting the values, 2 * 3.14 * 5 = 31.4 cm. Therefore, the correct answer is 31.4 cm.

Tags

CCSS.7.G.B.4

(Might need paper and pencil for this one!) What is the circumference of a circle whose diameter is 20 in? (Use 3.14 for pi)

• 31.4 in

• 62.8 in

• 3.14 in

• 64.7 in

Answer explanation

The circumference of a circle is calculated using the formula C = π * d, where d is the diameter. Substituting d = 20 in, C = 3.14 * 20 = 62.8 in. Therefore, the correct answer is 62.8 in.

Tags

CCSS.7.G.B.4

(Might need paper and pencil for this one!) What is the area of a circle whose radius is 1 in? (Use 3.14 for pi)

• 3.14 in

• 6.28 in

Answer explanation

The area of a circle is calculated using the formula A = πr^2. Substituting r=1, A = 3.14 * 1^2 = 3.14 in^2. Therefore, the correct area is 3.14 in^2.

Tags

CCSS.7.G.B.4

(Might need paper and pencil for this one!) What is the area of a circle whose radius is 2 in? (Use 3.14 for pi)

• 3.14

• 6.28

• 9.42

• 12.56

Answer explanation

The formula for the area of a circle is A = πr^2. Substituting r=2 and π=3.14, we get A = 3.14 * 2^2 = 3.14 * 4 = 12.56. Therefore, the area of the circle is 12.56 square inches.

Tags

CCSS.7.G.B.4

What is radius?

• The distance from the center to the rim of a circle

• A straight line going through the center of a circle connecting two points on the rim of circle.

• The distance once around the circle

Answer explanation

The radius is defined as the distance from the center to the rim of a circle, making it the correct choice.

Tags

CCSS.HSG.C.A.2

What is diameter?

• A straight line going through the center of a circle connecting two points on the rim of circle.

• The distance from the center to the rim of a circle

• The distance once around the circle

Answer explanation

The diameter is defined as a straight line going through the center of a circle connecting two points on the rim of the circle.

Tags

CCSS.HSG.C.A.2

What is circumference?

• The distance from the center to the rim of a circle

• A straight line going through the center of a circle connecting two points on the rim of circle.

• The distance once around the circle

Answer explanation

The circumference is the distance once around the circle, representing the total length of the circle's boundary.

Tags

CCSS.HSG.C.A.2