Surface Area Growing Post

Hello, this assignment is a growing post about the surface area of basic 3-D objects. First there is a rectangular prism with a net that contains a problem that I will solve using formulas. Then a triangular prism problem, then a cylinder, after that is two videos showing how I solved it. Before that though, I have to show and solve the three basic 3-D objects below.
This is a rectangular prism with its net (sorry the pictures are bad). A rectangular prism has two squares and four rectangles (or 6 rectangles). Now onto the problem part.

Here's the problem. I need one formula for each side of the prism. However I will do one of each type of side since I am not doing the same side again with the same calculations (makes my life easier and this post shorter). For rectangles and squares, the formula is length (L = length in short) multiplied by width (W = width). Then I am going to put the measurements in for the rectangle (any way does not matter). You can use a calculator if you want for this question (I used one too). In this problem, there are only two shapes with different measurements.

10.2 by 7.4 Rectangles

Rectangle = L x W

Rectangle = 10.2 x 7.4

Rectangle = 75.48m squared

4.7 by 7.4 Rectangles

Rectangle = L x W

Rectangle = 4.7 x 7.4

Rectangle = 34.78m squared

Now after finding all of the areas of the rectangular prism, I will add all of the areas up to get the total surface area of the rectangular prism (what I am trying to find) to finish the problem. There are four 10.2 by 7.4 rectangles and two 4.7 by 7.4 rectangles.

75.48 + 75.48 + 75.48 + 75.48 + 34.78 + 34.78 = 371.48

TSA (Total Surface Area) = 371.48m squared

The next 3-D object is an triangular prism. It has two triangles and three rectangles.

Scribepost

Today I had to do three questions on what we did recently in math class for scribepost today.

4. How many grids do each percent needs

a) 101%

We all know that 100% is one grid.

100 = 1 grid

101% is one percent higher than one hundred percent but we can not just put another square unit on to the hundred grid (same thing with alot of numbers) so we have to put another one hundred grid to cover that extra one percent.
X 101% = 1 grid (do not do this)
101% = 2 grids (putting another grid to cover the extra one percent is correct)


b) 589%

Again with the stuff above, 100% is one grid and why we can not increase the number of units in a grid. In other words we need to round up to the nearest hundred(always) and never round down. 589 rounded up is 600. Which means we need six 100 grids for this question. Then we just muliply one grid by 600 to complete the answer.

589 rounds up to the nearest 100 = 600
100 = 1 grid
1 x 600 = 600
600 = 6 grids

c) 1450%

Same thing with the other questions, we need to round up the number to the nearest hundred.

1450 rounds up to 1500
100% = 1 grid
1500 x 1 = 1500
1500 = 15 grids
10. A coach asked to give 110%.

a) Just find out the value of 110% in a fraction and in a decimal.

I first convent it into a simple fraction. Since fractions can be out of anything, I put the 110% on top because it is the value out of something. Then I put 100 on the bottom because percents are out of 100. Then from there, I have to simplify the fraction until it is in its most basic form. Dividing it by two is a very common way to simplify a number.

110 = 110/100
110/100 divided by 2 = 55/50

Fractions cannot have a decimal in it, so I had to use an alternative that if they have a relationship with each other we can divide it by the common muliple (relationship) to get a more simplified fraction. For this, they are both divisible by five so we can use it as the relationship. Then I can just divide the fraction by five.

55/50 divided by 5 = 11/10
The value is 11/10.
Now the fraction is in its most basic form (we cannot divide the fraction into another proper fraction; otherwise it is the answer). Now I have to find the value of 110% in a decimal.

Decimals are out of one and percents are out of one hundred. Do not worry, one and one hundred have a common mulitple between each other (by the way, its 100).

1 = 100%
110% divided by 100 = 1.1
110% = 1.1
The value is 1.1

b) What does the statement mean to you?

To me, the statement "Means give it all you got!!!" or "Give it your best!". In a more simple way, try your hardest. Now onto the last and final question I have to do for scribepost today.

14. Julia borrowed $100 from her brother. Julia's brother put a 5.5% interest for every month Julia did not pay him back (seriously, who does that!?). One month later, Julia paid her brother back. How much interest did Julia pay?

Well I solve questions like this in my way (simple, fast, shows you have done your work). I first find the percents I need and add them together to get the answer. There are other ways to get the answer, so you can do it your way when solving questions like these. I first find the five percent. Then I am going to find the half of a percent. After, I am just going to add them together to get the answer.I will not use ratio tables for this question, besides it saves alot of room. :)

$100 divided by 20 = $5
100% divied by 20 = 5%
$5 = 5%
Twenty mulipled by five equals one hundred. That is why I put twenty as the common muliple which I used to divide the number. Then I got the five percent I needed. Now I just have to find one half of a percent.

Both the 100% and $100 is the same so the results will be the same. I then am going to divide 100 by 100 to get one. After, I am going to divide it again by 2 to get one half of a percent.

$100 divided by 100 = $1
$1 divided by 2 = $0.50
$0.50 = 0.5%

Now I am going to add them up together to find the answer of this question.

$5 + $0.50 = $5.50

Julia paid an interest of $5.50

Thank you for reading my scribepost for today and farewell!!!!!

Kris, Runcel, Edmil Pay it forward

Part 1

Well about two weeks ago, every grade eight class saw a movie called Pay it Forward. In the movie, there was a kid who made up this method of everyone being kind to each other. One person had to do a kind thing to three different people and they have to do it too to spread across the globe. First it did not go well but in the end the kid was being interviewed and his idea to spread happiness and joy to the world was on television for many people to see. After that, the kid stood up for a poor kid being bullied three times. Sadly during the third time, the bully stabbed the kid and killed him but his idea will live on.

Part 2

What was your act of kindness?

My act of kindness is volunteering at the library.



Why did you chose this activity?



My first plan was to buy some non-parishible foods with some of my birthday money but i could not go with my mom for grocery shopping. I then just donated the money I was going to spend. Volunteering at the library with Runcel was my last option.

Who did you help?

We helped the librarian at the library.

What did you do?

We did some work in the library like putting away magizines and stacking chairs.

When did you do you act of kindness?

We did our act of kindness after school on December eight.

Part 3

How did your act of kindness go?

It went well, we did some work for about fifteen minutes

What happened?

We asked to volunteer at the library and did some work there too.

How did you feel?

I felt pretty good doing some work without any rewards.

How did that person react?

Well, she said thank you for volunteering.

Did you ask the person to pay it forward?

No, I forgot to tell her to "pay it forward".

How did they react to your request?

Since I did not ask the librarian, I would of not known their reaction to this request.

If you did not ask the people to "pay it forward", how come?

I did not ask to pay it forward because I forgot to tell her.

Part 4

Why is the idea of "pay it forward" important?

This idea is important because it teaches people to be more generous to each other.

Has your act of kindness made a difference?

Well yes it made a difference to many people, those who did not did their responsibility as a library helper and to others who I did not mention. Thank you for reading my post and goodbye!

Srcibepost December 3, 2009

Today in class, we did some questions from the textbook that some of us had a problem with. Then we learned how to make a good estimation of a square root. We did seventeen as an example.

First we found out that sixteen was the closest perfect square to seventeen. Sixteen has a square root of four.

We then found the next biggest perfect square. It was twenty five. It has a square root of five.


So now we know that the square root of seven is between four and five. Now what do you think is closer to seventeen, sixteen or twenty five.
The answer was sixteen. That would mean that seventeen has a square root that is close to 4. Since seventeen is one away from sixteen and we have lots of evidence, a good estimate should be four and one tenths. The square root of seventeen is really just about four and one hundred twenty three thousandths. That would mean we made a good estimate of the square root of seventeen.
Thank you for reading my scribepost for today. We also have to do pages twenty four and twenty five in our homework book for homework tonight or... since I posted this in the early morning, today before math class.