Granddad: Back in 1985 I played this guitar solo in Rio to a crowd of 100,000 people鈥︹
Grandmother: I used to bake鈥
Kids: Wow!!! Really!
Grandmother: Should I get my old rolling pin out and roll some pastry!?
Kids: YEAH!!!
Narrator: That鈥檚 right Granddad! Rock n Roll is over! All the kids want to do these days is BAKE!
V.O: Let鈥檚 kick some Cake!!
Narrator: Look at all those people there to see their hero. The edgy hard crust Baker himself, Simon the Pie Man.
Simon Pieman: Yeah, thankyou, Thankyou. Now I'm gonna show you my latest pie. It鈥檚 a concept pie.
I鈥檓 gonna show you that a PIE can be filled with INFORMATION! TASTY INFORMATION!!! Who鈥檚 with me!?Let鈥檚 make this pie, TOP OF THE CHARTS!
Narrator: Pie charts are brilliant at showing proportions, comparing the parts of something, because we鈥檙e very used to seeing actual pies being cut into portions. If someone said 鈥業鈥檒l halve this apple pie with you鈥 and offered you this much, you鈥檇 say ~
Youth: OI! That ain鈥檛 a half!
Narrator: And it鈥檚 because pie charts are so good at showing information, so easy to read, that you鈥檒l find they鈥檙e used a lot. So, you鈥檇 better know how they work! They can be cut into slices that are fractions, percentages or angles, but don鈥檛 panic! It鈥檚 easy when you get your head round it! Let鈥檚:
Narrator: Stroke the MATHS KITTEN for ANSWERS!
Narrator: Let鈥檚 start off slow. Let鈥檚 halve the pie. So we can express the slice of a pie as a fraction, a half; and because we can do this, we can also express fractions as percentages, so half is 50%, or in decimals, 0.5. And remember! A Pie is a circle, which is 360 degrees, so, we can also work out that the 2 pieces will be half of 360 which is 180 degrees.
It鈥檚 important to remember that Pie charts show data or information as proportions, not as actual amounts. Think of it as a whole pie showing you fractions, percentages or decimals as slices of the pie! To explain this better, bring me another pie!
This pie is cut into 5 slices we call sectors: a, b, c, d and e. We also know the angle of these sectors, A = 60o, B = 135o, C = 90o, D = 45o, E = 30o. But, if this Pie chart represents people, then C which is 90 degrees isn鈥檛 90 people. And 90 degrees isn鈥檛 90 percent! Be careful! Don鈥檛 mix up proportions with data! Infact, we don鈥檛 have any data yet, so let鈥檚 give you a clue
Narrator: This Pie Chart represents What Yesterday鈥檚 Lunch Queue Picked for Lunch. There鈥檚 a Key at the side.B represents 18 people. 18 people in the queue pick Pizza. But how many people in total were in the queue? Now, a lot of Maths is about using what you know to find out what you don鈥檛. Focus on what you know. That B is 18 people AND 135 degrees as a proportion of 360 degrees. So from this, you can work out the total number of people represented by the entire pie chart and then work out each sector. We do this by representing what we know as a fraction 135 over 360 which can be simplified by dividing by 5, which gives us 27 over 72 and then simplify again by dividing by 9; 3 over 8. So we know that 18 people are three eighths of the total. If we divide 18 by 3 to give us 6, we know that one eighth must be 6 people. Finally, to find out the total number of people we multiply 6 by eight to get 48.
SO 48 is our total number of people.
Simon Pieman: Whaaat! How many people had chips instead of healthy, healthy cake!?!??
Narrator: I don鈥檛 think cake鈥檚 that healthy.
Well, our magic ingredient for working out the other sectors is 48 over 360, which simplifies as a fraction to 2 over 15. Just work out 2 fifteenths of the other sectors. For example, A is sixty degrees. Two fifteenths of sixty degrees is 8. And so on.
Remember! Pie charts show proportions and don鈥檛 mix up your data with your percentages or angles or anything else! What do you think International Baking Sensation!?
Simon Pieman: Don鈥檛 mix your PIES! Goodnight!
Simon Pieman: And remember鈥on鈥檛 stage dive kids.
Sensi: My pupil, it is time for you to practice鈥 Fraction karate! Now chop the wood into thirds. And chop one of one of the thirds into quarters. Now what have you got?
Pupil: Very sore hands鈥 ARRGGGGGHH!!!
Commentator1: Some great fraction action, from the plucky pupil, there Brian.
Commentator2: Yes Brian, she certainly cut that plank of wood down to size. Let's have a look at that again in super slow mo.
Commentator1: There we see the plank being cut into thirds. Textbook!
Commentator2: And now she鈥檚 chopping one of those thirds into four pieces. She鈥檚 turned that piece into quarters with her bare hands Brian.
Commentator1: They鈥檙e not a bears hands Brian they鈥檙e a humans hands. And those pieces she just chopped are twelfths of the original plank.
Commentator2: Brian?
Commentator1: Yes Brain?
Commentator2 You鈥檝e really got to HAND it to her! HAND get it? HAND it to her. Haha ha ha ha haha!