📐 Circumference and Area of Circles

Master the key formulas and concepts for measuring circles using radius and diameter. **What you'll learn:** - Calculate circumference using $C = \pi d$ or $C = 2\pi r$ - Calculate area using $A = \pi r^2$ - Distinguish between radius and diameter in real-world contexts - Solve multi-step problems involving circles

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Question 1
Which measurement is the distance from the center of a circle to any point on its edge?
Question 2
The diameter of a circle is always twice the radius.
Question 3
A circle has a radius of $5$ cm. Its diameter is ___ cm.
Question 4
What is the circumference of a circle with a diameter of $10$ m? (Use $\pi \approx 3.14$ .)
Question 5
The area of a circle depends only on its radius, not on its diameter.
Question 6
A circle has a radius of $6$ cm. Its area is ___ $\text{cm}^2$ (use $\pi \approx 3.14$ ).
Question 7
A pizza has a circumference of $62.8$ cm. What is its radius? (Use $\pi \approx 3.14$ .)
Question 8
A circle with radius $4$ m has a larger area than a circle with radius $3$ m.
Question 9
A circular garden has a diameter of $14$ m. Its circumference is ___ m and its area is ___ $\text{m}^2$ (use $\pi \approx 3.14$ ).
Question 10
Two circles have the same circumference. What can you conclude about them?