# ISEE Upper Level Math : How to find the area of a sector

## Example Questions

### Example Question #1 : Sectors Give the area of the white region of the above circle if has length      Explanation:

If we let be the circumference of the circle, then the length of is of the circumference, so   The radius is the circumference divided by : Use the formula to find the area of the entire circle: The area of the white region is of that of the circle, or ### Example Question #1 : How To Find The Area Of A Sector The circumference of the above circle is . Give the area of the shaded region.     Explanation:

The radius of a circle is found by dividing the circumference by : The area of the entire circle can be found by substituting for in the formula: .

The area of the shaded sector is of the total area: ### Example Question #1 : How To Find The Area Of A Sector

While visiting a history museum, you see a radar display which consists of a circular screen with a highlighted wedge with an angle of . If the screen has a radius of 4 inches, what is the area of the highlighted wedge?     Explanation:

While visiting a history museum, you see a radar display which consists of a circular screen with a highlighted wedge with an angle of . If the screen has a radius of 4 inches, what is the area of the highlighted wedge?

To begin, let's recall our formula for area of a sector. Now, we have theta and r, so we just need to plug them in and simplify! So our answer is ### All ISEE Upper Level Math Resources 