This is a place for the community of learners in Room 8-17 to learn and enjoy math. It is an extension of the classroom making it accessible 24 hours a day, 7 days a week.
Sunday, October 31, 2010
Scribe 3
Determine the side length of a square with an area of 196 cm².
I used prime factorization to answer this:
The side length of a square with an area of 196 cm squared is 14 cm².
Page 85: Questions 3, 7, 12 and 14.
3. The square root of 36 is 6 because out of all the factors, 6 multiplied by itself is the only one that equalled to 36.
7. a) 2x3x7 = 42 ; It is not a perfect square.
b) 13x13 = 169 ; It is a perfect square.
c) 2x2x2x2x2x2x2x2 = 256 ; It is a perfect square.
12. Determine the square of each number:
a) 3x3 = 9
b) 18x18 = 324
14. Determine the side length of a square with an area of 900cm²
900 ÷ 30 = 30 ; 30x30 = 900cm²
The side length of a square with an area of 900cm² is 30 cm.
Here is a video on square roots.
Here is a link on square roots.
SCRIBE 5
18. The questions says that if the square floor mat has a side length of 14 m, what is the area of the square floor mat in square meters?
Here is my answer:
20. Now, this questions says that Adam's uncle has instructions for building a shed, but a page of the instructions was not as clear as he taught.
a) The questions asks for the area of the rectangle, and here is my answer:
b) This time , it asks for the side length of the square, and this is what comes up to my mind:
22. This number asks for three questions that are all connected to the largest in Beijing that has an are of 396, 900 m squared.
a) This question is asking about what are the dimensions of the square, and I answered,
b) This question asked if the dimension would be 629m by 629m, what would be the answer, and I answered this:
c)This question is asking if the area is less than 394, 000 but greater than 386,000,what will be the dimensions between those numbers, and I answered it like this:
Here's a link if you need help with finding area for rectangles or squares:
http://http//www.ehow.com/how_2256131_calculate-area-square-rectangle.html
And a video too,
Thanks for looking at my scribe, and don't forget to comment!
Saturday, October 30, 2010
SCRIBE 6
24. The first three triangular numbers are 1, 3, and 6.
A) What are the next three triangular numbers?
B) Add together any two consecutive
triangular numbers. What do you notice about the sums?
ANSWERS
A) 10, 15, 21.
B) The sums are all perfect squares.
27. A) Determine the square root of each number: 6400, 640 000,64 000 000.
B) Describe a quick method for determining mentally the square root of each numbe in part a).
C) Explain why this method does notwork for evaluating √640.
D)Use your method in part b) to evaluate √640 000 000 000 . Explain how you determine
the answer.
ANSWERS
27. A) √6400=80
√640000=800
√64000000=8000
B) First, ignore all the zero. Have you noticed that 64 is always there? If so, that means 8 is our first digit for each on of the square root. Why?Because the square root of 64 is 8. Next, pair all the zeros into 2. A pair of zero represents a zero after the 8. That means if there is 3 pairs of zero, then there will be 3 zeros after the eight.
C) The method I used can only work if all zeros have a partner.
D) First I ignore all the zero. I was left with 64.Since I know that the square root of 64 is 8. Then I already know that the first digit of my square root is 8. Next, I paired all the zero. I ended up with 5 pairs. Since I know that there are 5 pairs all I have to do is put them after 8. After all
those steps my answer is 80,000.
VIDEO:)
LINKS!!
How to find a square root without calculator
Friday, October 29, 2010
Scribe 4
17. The question asks to use prime factorization to figure out if 54 is a perfect square.
Here is the answer.
No. 54 is not a perfect square.
19. This question asks you to find the distince the students ran around the field twice.
This is the answer.
The students ran the distance of 1360 m.
21. The question asks you 3 things.1. That is the area of the patio.
Here is a picture of the patio.
Question 2 asks you to see if you can build another patio with the same area.
Question 3 asks you to make the patio into a square. Is it possible?
The answers
The area of the patio is 56 m2
Two examples for this is 7m by 8m and 28m by 2m.
It is not possible to make the patio into a square. Using prime factorization helps with this.
Here is a video on prime factorization and a link
Nino's, Math Profile
Last year, we did integers. It was easy, and we also used chips as an example on how use integers and the tests would be like free marks since it was so easy. I also liked areas of circles and squares, because we did the formulas and they were new to me. But I was kind of struggling on it since there were lots of formulas to remember.
This year I think I will do well on integers, since it's easy, but not on algebra. Algebra was kind of confusing and I did really do well on it last year, but this year i 'm going to try studying on it.
Last year when I was a blogger I got kind of confused on how make one, but the teacher helped me so I finished it on time. Blogging was actually kind of fun, and it felt good doing it for the first time.
Nino's Sesame Street Video
Part to whole ratio : Compares one part of the group to the whole group. It can be written as a fraction, decimal, & percent. (b:all letters, 5:8)
Rate; Compares 2 quantities measured in different units (2km/2hr)
Proportion reasoning : A relationship that says that 2 rates or ratios are equal. It can be written in fraction form. (2/3 = 6/9. (x3))
Part 2:
The Original Video:
Remake:
The Martians and The Math Book
Chris sesame street video
Part One :
Ratios:
Two term ratio ; Compares 2 quantities measured in the same units. (Eg A:B)
Three term ratio ; Compares 3 quantities measured in the same units.(Eg A:B:C)
Part to part ratio ; Compares different parts of a group to each other.(Eg A;B 2:4)
Part to whole ratio ; Ccompares one part of the group to the whole group. It can be written as a fraction, decimal, & percent.( A:all letters, 5:11)
Rates:Compares 2 quantities measured in different units.(Eg 4km/2hr)
Unit rate ; A rate where the second rate is 1.(Eg 10 letters/ 2hr)
Unit price ; Used when shopping.(Eg $o35/1mL)
Proportional Reasoning: A relationship that says that 2 rates or ratios are equal. It can be written in fraction form.(2/3 = 6/9. (x3)
remake :
Diana's Math Profle.
In Grade 7 I really liked learning about mean, median, mode, outlier, and range. The way Mr. Isfeld taught us, I could really remember. I also remember not being good at integers because I was gone while Mr. Isfeld taught the class, and I didn't ask the teacher & students for help.
This is now grade 8. I know that by finishing my homework, I will help me get a better grade in math. I also want to learn more about square numbers and square roots because I find it to be easy. I'm looking forward to doing Algebra in grade 9.
I was a blogger last year. http://room42math09.blogspot.com/2010/06/five-top-for-tests.html this post is about answering test questions also for exams. I like this post because it was really colorful and this was one of the best posts I've done. On this post I got 18 comments, it's not really though. This year, I hope I do a lot more posts and get a lot of comments.
Thursday, October 28, 2010
SCRIBE 1
HERE ARE SOME VIDEOS TO HELP YOU:
Karen's Square Root Scribepost
Here is a video if you want to understand it more.
Wednesday, October 27, 2010
Justin Lorenzo's Sesame Street Video
Me, Robin Apuya, Christopher Reyes
Part 1):
Two term ratio: Compares 2 quantities measured in the same units.
(eg. a:b)
Three term ratio: Compares 3 quantities measured in the same units.
(eg. a:b:c)
Part to part ratio: Compares different parts of a group to each other.
(eg. 1:3, c:d)
Part to whole ratio: Compares one part of the group to the whole group. It can be written as a fraction, decimal and a percent.
(eg. a:all letters, 5:10)
Rate: Compares 2 quantities measured in different units.
(eg. 5m/3s)
Unit rate: A rate where the second term is 1.
(eg. 3km/1hr)
Unit price: A rate used when you are shopping.
(eg. $2/100g)
Proportional Reasoning: A relationship that says that 2 rates or ratios are equal. It can be written in fraction form.
(eg. 1/2 = 2/4)
Part 2):
The original video was from Youtube. It is called "Sesame Street: Wanna Buy An Eight Earnie?
This is our remake video of "Wanna Buy An Eight Earnie?"
Find Factorization
√213 = 14._
√25 = 5
√72 = 8._
√850 = 29._
H.W.
On the long white sheet, finish the decimal square root and the fraction square root from numbers 1 - 25
Diorella's Sesame Street Video
Marie and I
Part 1:
Two term ratio: Compares 2 quantities measured in the same units. (eg. c:d)
Three term ratio: Compares 3 quantities measured in the same units. (eg. c:d:e)
Part to part ratio: Compares different parts of a group to each other. (eg. 2:4, c:d)
Part to whole ratio: Compares one part of the group to the whole group. It can be written as a fraction, decimal and percent. (eg. c:all letters, 10:21)
Rate: Compares 2 quantities measured in different units. (eg. 1meter/6s)
Unit rate: A rate where the second term is 1. (eg. 5km/1hr)
Unit price: A rate used when shopping. (eg. $3/100g)
Proportional Reasoning: A relationship that says that 2 rates or ratios are equal. It can be written in fraction form. (eg. 3/4 = 6/8 )
Part 2:
The original video is called, "Sesame Street: Pretend Teeth"
This video is about Abby and Elmo teaching everyone how to brush their teeth.
Part 3:
We did a remake on, "Sesame Street: Pretend Teeth"
Our video is about proportional reasoning and rates, and different kinds of examples.
Tuesday, October 26, 2010
Demvry's Sesame Street Video
Part to whole ratio : Compares one part of the group to the whole group. It can be written as a fraction, decimal, & percent. (b:all letters, 5:8)
Rate; Compares 2 quantities measured in different units (2km/2hr)
Propertion reasoning : A relationship that says that 2 rates or ratios are equal. It can be written in fraction form. (2/3 = 6/9. (x3))
Part 2:
The Original Video:
Remake:
The Martians and The Math Book
SQUARE ROOT
A square root is the opposite of squaring. So, instead to pressing the squared sign on the calculator, we press square root button.
HOW TO FIND A SQUARE ROOT
1) Get a calculator with square root function.
2) Since all calculators are different, try to press buttons until you get the answer. Maybe put number first, then the square root button or hit the square root button first then,the number. It all depends on how your calculator works.
3) Press the equal sign and "boom!" a bunch of numbers are on your calculators. You can round it to the hundredths though. Its easier to look at. It might not be the exact but, its close enough.
* ALL numbers have square roots. Its just that majority of them ends up with decimals.
EXAMPLE: Get the square root of 5.
1) On a calculator press √ then 5 or the opposite way.
2)Hit the equal sign button.
3)Once the answer appeared, round it to hundredths .
√3=2.23²
HOW TO ESTIMATE A SQUARE ROOT
To estimate a square root you may loo at the square root chart we made. Let's say we need to estimate what the square root 0f 570. We look at the chart and find what is closest products to 570. They are 576 and 529. Since 567 is closer, we choose that. 567's factors are 24x24, so that is an idea that the answer falls near 24.
EXAMPLE: Estimate the square root of 243.
243 falls between 225 and 256.Which is the product of 15X15(225) and 16X16(256.)Since, 256 is closer we
choose that. Now all we have to do is estimate what is the decimal needed.
ESTIMATING SQUARE ROOTS BY FRACTION
In this part, the number line we made would be helpful to us in this section.
Since there is 3 spaces between the first square root and the second square root. We would use 3 as our denominator.
1) 1/1 or 1
2)1 1/3 because, its in the first place after the perfect squared number.
3) 1 2/3 because, its in the second place after the perfect squared number.
4) 1 3/3 or 2 because, the square root of 4 is 2.
*Take note that we always don't use 3 as the denominator. It depends on how many spaces are there between a perfect squared number to another.
HOMEWORK
Use fractions to estimate the square roots of 1-25.
How can you use perfect squared numbers to estimate square roots?
Still having trouble? No problem!I provided links and video to help you understand more!:)
LINKS:
SQUARE ROOTS GAME
HOW TO ESTIMATE
VIDEO:
(I wanted to put the real video. However, it wont work and there's errors..)
Kathryn's Sesame Street Video Post
1:5
1 : 2
REMADE VIDEO
We also made a tagalog version. ENJOY!
Monday, October 25, 2010
Kaecee's Perfect Squares Scribe Post
Sunday, October 24, 2010
Saturday, October 23, 2010
Thessa's Square Numbers Scribe Post
Wednesday, October 20, 2010
Karen's Sesame Street Video Post
Thessa Baldo-Oduca
Windy Tabaquero
Karen Sule
Ratio:
two-term:Compares two quantities in the same units.(red shoes to blue shoes,5:7)
three-term:Compare three quantities in the same units.(red shoes to blue shoes to black shoes,5:7:8)
part-to-part:Compares different parts of the group to each other.(red hat to white hat,2:3)
part-to-whole:Compares one part of the group to the whole part of the group. It can be written as fraction,decimal and a percent. ( red hat to all hats. 2:10)
Rate:Compares2 quantities measured in different units.
unit rate: A rate where the second rate is one. (10 letters/1 minute)
unit price:Used when shopping.($0.95/2ml)
Proportional Reasoning: A relationship that say 2 rates or ratios are equal. It can written in fraction form. 3/9 = 9/27 x3
Original video:
Cookie Monster Question Prairie Dawn
Remake:
Casey's Sesame Street Video
Part to whole ratio : Compares one part of the group to the whole group. It can be written as a fraction, decimal, & percent. (b:all letters, 5:8)
Rate; Compares 2 quantities measured in different units (2km/2hr)
Propertion reasoning : A relationship that says that 2 rates or ratios are equal. It can be written in fraction form. (2/3 = 6/9. (x3) )