# GED Math : Radius and Diameter

## Example Questions

### Example Question #21 : Radius And Diameter

Determine the radius of the circle if the diameter of a circle is .

Explanation:

The radius is half the diameter.

Multiply the diameter by one-half.

### Example Question #21 : Geometry And Graphs

Find the diameter if the radius is .

Explanation:

The diameter is double the radius.

Do not multiply the coefficient into the radical.

### Example Question #23 : Radius And Diameter

Determine the diameter if the radius is .

Explanation:

The diameter is double the radius.

Substitute the radius into the formula.

### Example Question #981 : Ged Math

A circle is circumscribed in a square as shown by the figure below.

If the area of the square is , what is the area of the circle in square inches? Use .

Explanation:

Start by finding the length of a side of the square from the area.

Plug in the area to find the length of the side.

Now, notice that the diameter of the circle is the same as the length of a side of the square.

Thus, the diameter of the circle is , which means the radius is . Recall how to find the area of a circle:

### Example Question #25 : Radius And Diameter

Determine the diameter with a radius of .

Explanation:

The diameter is double the radius.

### Example Question #991 : Ged Math

Determine the radius if the diameter of a circle is:

Explanation:

The radius is half the diameter.

Multiply the diameter by one-half.

### Example Question #21 : Radius And Diameter

Determine the radius of the circle with a diameter of .

Explanation:

The radius is half the diameter.  Multiply the given diameter by half.

### Example Question #21 : Geometry And Graphs

You have a giant gong that has a diameter of . Find the radius of the gong.

Explanation:

You have a giant gong that has a diameter of . Find the radius of the gong.

To relate radius and diameter, use the following formula:

So, to find our radius from our diameter, divide by 2:

### Example Question #29 : Radius And Diameter

While doing your homework, you become distracted by the 3 holes on the margin of your paper. You estimate that the holes have a diameter of 2.5 cm. What is the radius of the circles?

Explanation:

While doing your homework, you become distracted by the 3 holes on the margin of your paper. You estimate that the holes have a diameter of 2.5 cm. What is the radius of the circles?

Recall that your radius is always exactly half of the diameter. A diameter spans the entire width of a circle, while a radius goes from the center to the edge.

So, to find our radius, divide our diameter by 2

### Example Question #992 : Ged Math

What is the radius of a circle if it has a circumference of ?