Task Sets: Circumference and area - ACT Math

Recall / Warm-Up

A circle has a diameter of 14 cm. What is the radius?

7 cm

14 cm

28 cm

3.5 cm

What is the perimeter of a square with side length 8 cm?

16 cm

32 cm

64 cm

24 cm

What is $7^2$ ?

A circle has radius 5 cm. What is the circumference? Express your answer in terms of $\pi$ .

A circle has diameter 18 in. What is the circumference in terms of $\pi$ ?

$9\pi$ in

$18\pi$ in

$36\pi$ in

18 in

A circle has radius 6 cm. What is the area? Express your answer in terms of $\pi$ .

A circle has diameter 10 m. What is its area?

$100\pi$ m²

$25\pi$ m²

$10\pi$ m²

$50\pi$ m²

A circle has radius 9 cm. What is the circumference? Round to the nearest tenth. (Use $\pi \approx 3.14159$ .)