# Radius - Examples, Exercises and Solutions

The radius is one of the many elements that exist in a circle. The radius is a segment that connects the center of the circle with any point located on the circle itself. Each circle has an infinite number of radii and their length is exactly the same, that is, they are identical.

The radius is used to calculate the diameter and perimeter of the circle, it is also used to obtain the area of the circle.

Below are several examples of different circumferences.

The colored parts are, in fact, some radii painted on each circumference:

The colored parts are, in fact, some painted radii on the circumference:

### Exercise #1

There are only 4 radii in a circle.

### Step-by-Step Solution

A radius is a straight line that connects the center of the circle with a point on the circle itself.

False

### Exercise #2

M is the center of the circle.

In the figure we observe 3 diameters?

No

### Exercise #3

Is there sufficient data to determine that

$GH=AB$

No

### Exercise #4

M is the center of the circle.

Perhaps $MF=MC$

Yes

### Exercise #5

M is the center of the circle.

Perhaps $AB=CD$

No

### Exercise #1

In which of the circles is the center of the circle marked?

### Exercise #2

M is the center of the circle below.

$AB=10$

Can a chord with a length of 15 cm be drawn in the circle?

No

### Exercise #3

M is the center of the circle shown below.

AB is a chord in the circle and is 8 long.

Which of the options is a reasonable length for circle's diameter?

### Video Solution

$16$

### Exercise #4

Fill in the corresponding sign

$\pi?3.147$

### Video Solution

$=$

### Exercise #5

Fill in the corresponding sign

$\pi?3.2$

<

### Exercise #1

Is it possible for the circumference of a circle to be $10\pi$ if its diameter is $2\pi$ meters?

No.

### Exercise #2

Is it possible for the circumference of a circle to be $5\pi$ meters if its diameter 5 meters?

No.

### Exercise #3

Is it possible for a circle to have a circumference of 314.159 meters (approximately) and a diameter of 100 meters?

No.

### Exercise #4

Is it possible that a circle with a circumference of 50.6 meters has a diameter of 29 meters?

No.

### Exercise #5

Is it possible that the circumference of a circle is 8 meters and its diameter is 4 meters?