00:01in this video we will learn all about

00:04pie charts a pie chart is a type of

00:07graph that shows the relative sizes of

00:12visually a pie chart is made on a circle

00:16and the reason it's called a pie chart

00:19is because with all of the pieces in

00:21there and the different data it can sort

00:23of look like a pi so let's look at an

00:27example of some data here here's some

00:30data from a recent election we have four

00:33students A B C or D and we have the

00:37percent of votes that they received in

00:39the election so student a got 30%

00:42student B got 50% and so on so we could

00:47represent this with a pie chart which

00:48would be a nice visual way to see how

00:52many more votes student B got compared

00:56others so there's two ways you can think

00:59about making a High chart you can either

01:02it with the hundreds disc method or the

01:06circle method depending on whether you

01:09want to think in percents up to 100% for

01:13the whole circle or in degrees up to

01:16360° in the whole circle so the circle

01:19on the left is broken into 100 different

01:22pieces and so this would be the hundreds

01:25method and we could use the circle

01:27method for the other Circle so let's

01:29start with the hundreds method we have

01:31student a got 30% of the votes so we

01:34want to shade in or color in 30% of our

01:38Circle for student a and label that with

01:40student a so you want to pick a color

01:44and each of these big wedges is 10 so I

01:48can just take three of those and this is

01:5230% of the circle and therefore

01:55represents student a now I can go on to

01:59student B who got 50% of the votes I'm

02:02going to pick another color and shade in

02:0550% of the circle for student B so

02:08remember 50% is half the

02:11circle or five of these

02:14wedges and don't forget when you make a

02:16pie chart to label your different

02:18sections or it will have little meaning

02:21or you can make a key off to the side

02:24too now we have student C got

02:2815% so that's a whole wedge plus a half

02:36one and finally student D got

02:415% so student D is this last part right

02:46here make sure that all your percentages

02:49add up to 100% or else your whole graph

02:53won't really make sense or your whole

02:57chart and again the nice thing thing

02:59about a pie chart is it's very Visual

03:02and you can see from the pie chart how

03:05much bigger student B's area was

03:09compared to the others now if you use

03:11the circle method your result will be

03:13the same it's just sort of an how you

03:16think about it if you're thinking about

03:17it in terms of percentages or in terms

03:19of degrees so if you wanted to do the

03:22circle method you might start by

03:23thinking okay student B got 50% so

03:27180° or half of the circle and I might

03:30do them student B first and draw in a

03:35diameter and know that half of the

03:40180° is student B and then for student a

03:44which is 30% you'd have to figure out

03:47how many degrees is 30% of a whole

03:50circle so A whole circle is

04:00108 so you would want to use a

04:02protractor to measure out

04:06108° of this circle so maybe starting

04:09from this line right here measure

04:13108° to figure out where the next line

04:16should go so you have to have a

04:17protractor to be able to use that method

04:20and this is student a and then you would

04:24do the same thing for C and D okay 15%

04:30that is 54° and you'd use your

04:33protractor to measure

04:3554° and whatever is left should be the

04:38right thing for student D so the circle

04:41method works if you have a protractor if

04:44you don't then sometimes it's easy to

04:47just eyeball it or if you have computer

04:51that's an easy way to make sure it's

04:53actually completely accurate when you're

04:55making the pie chart especially if

04:57you're dealing with percentages that are

04:59more than than just 25% or 50% that are

05:02not too hard to sketch out