The picture shows a circle divided into 8 equal wedges, which are rearranged.

Two shapes. The first shape is a circle divided into 8 identical wedges. The second shape is the same 8 wedges arranged horizontally, alternating between wedges with their arc ends on top and wedges with their arc ends on the bottom, making a shape somewhat like a rectangle.

The radius of the circle is \(r\), and its circumference is \(2\pi r\). How does the picture help to explain why the area of the circle is \(\pi r^2\)?

A paper plate has a radius of 4.5 inches. What is the area of the plate?

Jada paints a circular table that has a diameter of 37 inches. What is the area of the table?

A circle’s circumference is approximately 76 cm. Estimate the radius, diameter, and area of the circle.

Which of these pairs of quantities are proportional to each other? For the quantities that are proportional, what is the constant of proportionality?

1. Radius and diameter of a circle
2. Radius and circumference of a circle
3. Radius and area of a circle
4. Diameter and circumference of a circle
5. Diameter and area of a circle

Here are the diameters of four coins:

1. A coin rolls a distance of 33 cm in 5 rotations. Which coin is it?
2. A quarter makes 8 rotations. How far did it roll?
3. A dime rolls 41.8 cm. How many rotations did it make?

Andre has a goal to exercise for 60 minutes this week. How many minutes has he exercised by each day?

1. By Monday he has exercised for 10% of his goal.

2. By Wednesday he has exercised for 60% of his goal.

3. By Saturday he has exercised for 130% of his goal.