A Pecha Kucha (20 slides in 6 minutes) presentation meant to be a useful introduction and overview for a 7th grade middle school mathunit on Ratios, Proportions, and Probability
6. Rates and Lightning
Lightning strikes somewhere on
the earth at a rate of 6002
times per minute!
As you watch lightning
strike, listen for the thunder!
For every 5 seconds between a
flash and the sound of thunder,
there is 1 mile between you and
the strike.
13. Sample Spaces
If you roll a die, the sample space is {1, 2, 3, 4, 5, 6}.
(It's a fancy word for 'all possible outcomes'!)
If you roll two dice, the sample space
is the whole numbers 2-12
14. Simple Events: Probability Basics
All outcomes are equally likely to happen
Ex. Rolling an
even number
using a die.
It is equally likely
that you roll any
of the 6 numbers
15. Another “Simple Event”
The pieces of the pie are all the same size,
so they all have an equal chance of happening
16. The Fundamental Counting Principle
What are all the different possible outcomes
you can get if you flip a coin and roll two dice?
You just multiply the number of possible outcomes from each
Event involved!
17. The Fundamental Counting Principle
Basically, if you have x ways of doing
one thing, and y ways of doing
another, then there are x times y
ways of doing both things.
Relates to probability: What is the probability of you
getting both your dice to land on 3 in the last
experiment?
18. Types of Probability
What should happen?
Ex. How many times should you expect to get
heads if you flip a quarter 50 times?
THEORETICAL
PROBABILITY
19. Types of Probability
What actually happens when you
perform an experiment?
Ex. How many times do you ACTUALLY get
heads if you experiment by flipping the quarter
50 times in class?
Experimental
Probability
21. intmath.com – Golden Ratio Man
www.curly-hair-styles-magazine.com – Marilyn
www.contactmusic.com - Lady GaGa
library.thinkquest.org – mona lisa
www.tvscoop.tv - Clarkson going fast
www.scienceblogs.com -pie
www.caption-this.com – dice
www.pwcphoto.com - dice
houseofmashinchi.blogspot.com – spinner
www.pokerxclusive.com - poker hand
Editor's Notes
Describe: Why they are all in one unit? All about comparing things: comparing two things from the same group (like comparing students from my class to students from another teacher's class), comparing two things that are very different (like comparing people to weight), seeing how two things change (how often they change, how drastic they change) and if they change the same over time. Then, we will think about how things change to PREDICT THE FUTURE!
Ratios:
-Ratios are how you compare two things that are the same
-Example of ratios: comparing gallons of milk to gallons of OJ
-comparing similar stats of different Athletes (like how far certain runners ran in the same period of time)
-math history=golden ratio=the idea that all limbs on a human being have a ratio that are the same magic number, and that this was the idea of the “perfect” human being. (note Da Vinci and artwork, statues, sketches)
Also, the construction of the Egyptian pyramids are analyzed by math people in terms of the golden ratio
A special kind of ratio is known as the Golden Ratio. This is an extremely famous ratio discovered in math history by a dude named Fibonacci. It is pretty much determining two numbers whose combined length satssfies the ratio shown. The ratio of the whole length to the long part is equal to the long part to the short part.
---human portraits (Golden square of Mona Lisa's face, ratio of upper torso to bottom torso)
----sunflower seeds spiral out from the center in two directions one direction spirals with 21 seeds, the other spirals with 34. These numbers create the golden ratio as well.
Rates: a type of ratio that compare two different things.
--instead of comparing stats of two athletes, you could compare number of baskets made per minute. (comparing baskets and minutes)
--the most common application of rates is in cars...fast cars! MPH, KMH (in europe)
--with rates comes something called rate of change:it's like walking on a hill; if the hill is changing very quickily uphill, then it has a large rate of change. If the hill is the same all the way up, then it has a constant rate of change. If the hill is going down, then it has a negative rate of change. like the height of someone changing over time. Rate of change usually looks at a pattern over time.
Another example: distance you have traveled on a bike over time. Think about it, you get tired! So your rate of change will get slower over time because your legs get tired
Rates are all over the world, just like lightning! You can use rates to see how often something happens (like per minute, per hour, per day, per year)
According to scientists, lightning strikes on earth about 6002 times every minute!
Along with lightning, meteorologists use rates to describe how fast a tornado is moving, which direction it is moving in, and how fast its winds are blowing.
Chances are, if the tornado is blowing harder than 50 mph, you will want to seek shelter
Scale drawings:
--can also use ratios to draw things according to a scale.
EXAMPLE: Map/globe. Ever wonder how people tell how far a distance is just by looking at a tiny map? The people who make the map draw it to a “scale” (circle scale on the Google Map)
The same thing happens for designing models. Architects draw houses to scale, and use that scale to make the actual house.
You can draw something really small to represent something really big.
Designing boats, houses, basketball courts, tables, even electronics.
You will most certainly learn about probability, and so you have a 100% chance of learning about probability!
Probability covers all sorts of situations, but is seen largely in games. Games of chance like poker and rolling dice are common. In poker, what is the chance that you are randomly given the 4th king if another player already has 2 kings? Also, think of the show The Price is Right. What is the chance you will guess the right price out of 5 possibilities?