This worksheet is about finding the areas of circles.

You must learn this important formula for a circle of radius, r :

Area of a circle = π r^{2}

What is pi (π) in numbers? Pi is an infinite number, and you can use a function on your calculator to input the number.

**Here is the start of it - 3.14159265359...**

In this activity, you will **need to use a scientific calculator** to calculate the answers. You can use one **online **if you do not have one in your home.

**Example**

Find the area of a circle of radius 6 cm.

**Answer**

**Area = π r ^{2}** = π × 6

^{2}= π × 36 =

**113.097335529**

We need to give our answer to 1 decimal place (this means if the second number after the decimal point is 5 or higher then we round the number **straight** after the decimal point up one number, if the second number after the decimal point is less than 5 we leave the number after the decimal point the same).

**Area = π r ^{2}** = π × 6

^{2}= π × 36 =

**113.1 cm²**

**Remember, in this activity, you need to use a scientific calculator to calculate pi correctly, you can access one of these online.**