Tutorial

**Key Ideas:**

**Circle graph** - shows how the parts of a set of data compare with the whole set of data

**Here is an example to work through and try!!**

Example: I asked 100 people what is your favorite color.

**To draw a circle graph:**

**Step 1**: Create a table like the one below (if it is not already given to you).

**Step 2:** Write each number as a fraction of the sum of the numbers in the data

- 20 out of 100 people like Red so this fraction would be
- Blue the fraction is
- Green the fraction is

**Step 3:** Write each fraction as a percent (this is easy for this example since the denominator is already 100)

- Red is 20%
- Blue is 45%
- Green is 35%

**Step 4:** Write each fraction as a decimal, then multiply by 360^{o} to find the size of each angle needed for the sectors

- Size of angle for Red is 0.20 x 360
^{o}= 72^{o} - Size of angle for Blue is 0.45 x 360
^{o}= 162^{o} - Size of angle for Green is 0.35 x 360
^{o}= 126^{0}

**Step 5:** Use your protractor to draw the angles in a circle like the one below. You can either draw your own circle or your teacher can provide you with a copy of it. Start by drawing the radius of this circle. Try it on your own! If you need help see your teacher the next class.

**NOTE:** GO BACK TO REVIEW HOW TO USE A PROTRACTOR AT THE BEGINNING OF THIS UNIT (VIDEO 1)