Sunday, October 21, 2012
Wednesday, October 17, 2012
ratio: It compares different parts of a whole, it is similar to a fractions
rate: Compares two quantities measured in different units.
proportion: A proportion makes a equivalent fraction in the same units they where already in.
Ratio ex: 1:4 blue balls to red balls, this means for every blue ball there are 4 red balls.
Rate Ex:$/H this means if a how much a worker earns per hour.
Proportion Ex: Km/H this means how many km a car can travel in one hour.
- 5 hours to travel 360 kilometers is about _____km/h.
- 5H/360km= ?/720 5x720= 3600 divided by 360= 10 10 hours to travel 720km. 10 divided by 10 =1 and 720 divided by 10 = 72km 72km/H
- Emma saves 28 cents of every dollar that she earns. Emma earned $75 last week. How much money did Emma save last week?
75 divided by 0.28x75= 21 dollars
3/4 = 12/16 is false because 3x4= 12 but 4x3=12 not 16 which proves its not equivalent.
- It doesn't look fair but I think the judge was just being nice to the homeless guy.
- it isn't fair because the other guy was going to steal much more than the homeless guy and the homeless guy gave it back.
- so the homeless guy gets food in jail and shelter
- I would do the same so the homeless guy can survive in jail.
Joel's Proportion Post
Part 1- DefinitionsRate- Comparison of the two quantities measured in different kinds of subjects, such as kilograms, hours, grams etc.
A guy ran 22 laps in 7 minutes. How many will he run in 14 minutes?
Soda's to Oranges Oranges to Soda's
Proportion- It is two equivalent fractions, ratios, and rates
I ate 10 chocolate bars in 40 minutes.
My proportion is that i ate 1 chocolate bar every 4 minutes.
Part 2- The questionsA) 6 hours to drive 240 hours is 40 km/h
B) Emma saves 28 cents of every dollar that she earns. Emma earned $75 last week. How much money did Emma save last week?
Part 3- Equivalent ratio statement3/4=12/16
The fraction 4/9=16/32 are not equivalent fractions
- Does this seem fair?
- With what you know about proportion look and read what is in the image above. Does it seem just and fair?
- Why have you made this choice?
- What would you have done if you were the judge?
Tuesday, October 16, 2012
Kyle's Proportion Post
Proportion - When two ratios are equal and the cross products are equal
Part 2: Questions
1. 5 hours to travel 360 kilometers is about ____ km/h
2. Emma saves 28 cents of every dollar that she earns. Emma earned $75 last week. How much money did Emma save last week?
Part 3: Equivalent Fractions4/9 is not equivalent to 16/32
Part 4: Proportion video
Does this seem fair?
No, this is not fair in many ways.
With what you know about proportion look and read what is in the image above. Does it seem just and fair?
He stole 100 dollars and sent 15 years to prison. I turned the 5 years into days so 5475 is equal to 15 years. I divided 100 dollars by 100 to make 1 dollar and divided 5475 by 100 and made 54.75. 54.75. I rounded up the 54.75 to closest whole number and came up with 55. Its not fair to be in jail for 55 days for stealing a dollar or 15 years of jail by stealing a 100 dollar.
Why have you made this choice?
The man was poor and sad and was desperate for money like every homeless people is but even if he stole the money. He was honest and went to the police to admit what he has done.
What would you have done if you were the judge?
I would have done some thinking alone and thought smart about what he was about to do to a poor honest man.
Rate-A quantity measured with respect to another measured quantity
5hours to travel 360 kilometers is about _____km/h
360\5 = 72 km per hour .
Emma saves 28 cents of every dollar that she earns. Emma earned $75 last week. How much money did Emma save last week?
· Does this seem fair? No
Monday, October 15, 2012
|The relationship between two measures, |
expressed as the number of times one is bigger or smaller than the other.
Consider the two bars on the right. One has a height of 10 meters the other 40 meters. The taller one is obviously four times taller than the other, so we say thier heights are in the ratio of four to one. What this means is that for every one unit of height on the left bar, the tall bar has four height units. Hence "four to one".
Using a colonRatios are usually written as two numbers separated by a colon:
the ratio of their heights is 4:1The colon between the 4 and 1 is read as "to". So the sentence would be read as
"The ratio of the heights is four to one".Obviously the taller one is first here. If you considered the smaller bar first then the ratio would be 1:4.
As a fraction
Using the bar example again, we ca also write the ratio as a fraction, where the top (numerator) is one height, and the bottom (denominator) is the other. We can pick either one to be the top, so using the smaller one, we can write:
the ratio of their heights iswhich reduces to .
This fraction can then also be written as a decimal. In this case 0.25. This would be read as "the smaller bar is 0.25 times the height of the larger one"
Ratios have no units
A ratio is how many times bigger one thing is than another. It's a number you multiply by to get one thing from another. But remember, when you find the ratio of two quantities, they must be in the same units.
It's easy to get ratios backwards
If you know that John and Jim have weights in the ratio 1.2 : 1, there can be confusion about whom is the heavier of the two. By convention we assume that since John is mentioned first then his weight is the 1.2 in the ratio since that is also first. But you should be as explicit as you can. It is better to say John's weight is 1.2 times Jim's.
When the ratio is expressed as a fraction, the convention is that the first mentioned item is on top (numerator).
Don't confuse ratio with differenceThe bars above have heights in the ratio 4:1, but the difference in their height is 30 meters.
- Rate is a ratio that compares two quantities of different units.
- 20 oz of juice for $4, miles per hour, cost per pound etc. are examples of rate.
- Unit rate: Unit rate is a rate in which the second term is 1.
For example, Jake types 10 words in 5 seconds.
Jake’s unit rate is the number of words he can type in a second.
His unit rate is 2 words per second.
"4 lb of meat costs $5." Identify the two rates given by the statement.
D. none of these
Correct Answer: A
Step 1: Rate is a ratio that compares two quantities of different units.
Step 2: The two rates given by the statement are and .
- two equal fractions,
- using a colon, a:b = c:d
That is, for the proportion, a:b = c:d , a x d = b x c
a. six pairs of shorts cost $96. How much will nine pairs of shorts cost?
b. Carmen used a 5ft of string to make 4 mobiles. how much string will she need to make 18 mobiles?
c. five art magazines cost $14.25. how much will eight art magazines cost?
d. four baseball caps cost $25. how manny baseball caps can you buy with $43.75?
c). 5 mags cost $14.25. 8 mags should cost $14.25 x 8/5 = $22.80
d) 4 caps cost $25. You can therefore buy 4 x 43.75 / 25 caps = 7 caps
e) no answer - The fact that two helicopters were used in three hours does not mean that 2 x 12 /3 =8 helicopters are used in 12 hours. The same two helicopters may be used for the entire 12 hour period. There may only be 2 helicopters.
For example :
a rate of 30 miles per hour.
Here is a video and a picture for more help :
What is a ratio?
A ratio is when you compare 2 quantities.
For example : the ratio for red circles to clue is 4:6 .
A proportion is like a part in relation to the whole.
for example :
5hours to travel 360 kilometers is about _____km/h .
360\5 = 72 km per hour .
Sunday, October 14, 2012
Defining ratios, rates, and proportions.
A ratio is a relationship between two quantities.
For 3/4 = 12/16 and 4/9 = 16/32.
You can solve the problem using horizontal method, cross method and the baseball bat method.
The other fraction, 4/9 = 16/32 are not equivalent fractions because I've tried the three methods above and they haven't worked on this proportion.
1. Does this seem fair?
In my opinion, it's not fair to make someone spend 15 years in prison for stealing something then surrendering. Because in the end he was true and honest.
2.With what you know about proportion look and read what is in the image above. Does it seem just and fair?
No, because he was given three stacks of bills but he only took $100. 15 years in prison isn't fair, especially since he surrendered at the end.
3. Why have you made this choice?
Because this guy's actions were of good intention. He needed the money then confessed after he felt guilty.
4.What would you have done if you were the judge?
I would have taken off 13 years off his time in prison, at the very least, because he only took $100 out of three stacks.
Q: How tall are the trees?
A: I estimated the kid (Who looks about 12 years old) to be about 5ft tall.
I used my thumb to indicate how many kids it would take to reach the height of one of the trees.
It takes about 3 and a half kids.
5 x 3.5 = 17.5
So the trees are about 17.5 ft