## Thursday, March 25, 2010

### Deniel's surface area growing post

Okay guys here is my surface area growing post about right rectangular prism, right triangles, and cylinders

Here is my first surface area question:
Okay here is what I did:

front:
13.5 cm x 18.5cm =area 13.5 x 18.5= 249.75cm x 2 = 499.5cm
side:
5 cm x 13.5cm =area 13.5 x 5= 67.5cm x 2 = 135cm
length:
18.5 cm x 5cm =area 18.5 x 5= 92.5cm x 2= 185cm

499.5+135+185= 819.5
Area= 819.5cm

Here is my second question:
Okay so here's what I did:

A= l x w A= (b x h) / 2
A= 9 x 3 A=(3 x 2.6) / 2
A= 27 The area on one rectangle is 27m A=7.8 / 2
A=3.9 and its the area of one triangle

Surface Area= (3 x rectangle) + (2 x area of triangle)
= (3 x 27) + (2 x 3.9)
= 81 + 7.8
= 88.8
So the surface area is 88.8 centimetre squared.

Here's my third question:
Here's what I did:
Determine the radius of each circle:
7.5 / 2 = 3.75 so 3.75 is the radius of each circle

Find the area of the circle
A=π x r2
A=3.14 x 3.75 x 2
A= 44.15625 so the area of one circle is 44.15625 x 2 = 88.3125 for both circles.

Find the area of the rectangle using the circumference of the circle.
A= l x w
A=(π × d) × w
A= 3.14 × 7.5 × 11
A= 259.05
The area of the rectangle is approximately 259.05 cm2.

Calculate the total surface area.
Surface area = 88.3125 + 259.05
= 347.3625
The total surface area is approximately 347.36 cm2

So here is my surface area growing post :)

### Surface Area Growing Post

Heey guys!! sorry this post maybe late but I managed to finish it on time (:

The calculations for the triangular prism is
10cm , 12cm 4cm , and 5cm .

P.S - sorry if you cant read either one of these questions.

AND please correct me if you see anything wrong

## Wednesday, March 24, 2010

### Nhea's Growing Post 3/24/10

A)

B)To get the answer to this Question -

All you have to do is multiply the first number (4) by the numerator (1) but the demoniator always stays the same so you would get the answer (4/2) then you have to simplify if possible (1 2/2).
C)To Answer this question -All you have to do is use a picture (or number line) to determine the answer. Using a picture all you have to do is make a square. The number of squares going down is the same number as the single number (2) and the squares going across is the same number as the first denominator (4). Then shade in the the number of the single number (2) and use a different colour to shade in the number of the numerator (1) over the already shaded part to get your answer (1/8)

D) To answer this question -
All you have to do is shade in the number of squares that match the single number, 5, then use a different colour to re-shade the number that is the numerator, 1. Then you would get 1/15 as your answer.
Part 2

Fractions

### Althea's Fraction Growing post

HELLO EVERYONE :D

page 202, question 6

a.) 4 x 1/2

b.) 3 x 7/10

c.)5 x 2/3

this is a different way to solve the problem

5/1 x 2/3

so i mutiplied numerator which is 5 x 2= 10
then i multiplied the dinominator which is 1 x 3= 3

10/3

10 divided by 3 = 3 1/3

d.) 3 x 3/8

3 x 3= 9

1 x 8= 8

9/8.....9 divided by 8= 1 1/8

page 208 question 5

a) 3/5 dvided by 2

b.) 1/5 divided by 3

c.) 1/2 divided by 4

d.) 2/3 divided by 6

page 208, question 7 (word problem)
____________________________________
Part 2

Part 3

Explain:

1 1/2 divided by 3/4

• Find the lowest common denominator (LCD).
•Lowest common denominator of 2 and 4 is 4

___________________________________________________________
3/4 divided by 1/2

•Find the LCD ( lowest common denominator)
•LCD of 4 and 2 is 4

1 x 2=2
2x2=4

Now, we have to know how many 2/4 goes into 3/4.

### Fraction Growing Post

For Fractions I'm doing is Questions 6. determine each product using manipulative or diagrams

a) 4x1/2 b) 3x 7/10

c) 5x 2/3 d) 3 x 3/8

Then I'm going to show you how to divide Question 5-4
a) 1/4 } 2 b) 1/3 }3

c) 1/5 }2 d) 5/6 }4
Question 5 .
a) 3/5 } 2 b) 1/5 } 3

c) 1/2 }4 d) 2/3 } 6

Fraction part #2 MULTIPLYING Mixed fraction, Improper fractions and Proper fraction.
Proper Fractions
Questions through 3-11
3.
a) 5/6 x 1/2 = 5/12 b) 3/4x 5/6 = 15/24.

The step is to multiply the numerator and the denominator.
4.

a) 1/4 x 2/3= 2/12 or 1/6 b) 7/10 x 1/2= 7/20

5.

a) 3/8x 2/3= 6/24 b). 3/7 x 1/6 =3/42 c) 3/4 x 3/4= 9/16

6.

a) 2/5 x 4/5 =8/25 b) 7/8 x 4/5 = 28/40 c) 3/4 x 4/9 = 12/ 36

7. Tamar had 1/2 of an apple pie in her refridgerator. She ate 1/4 of this pie.

1/2 x 1/4 = 1/8 8. 1/3 x 1/4 = 1/12 9. 1/20 x 1/10= 1/200 10. 3/5 x 1/2 =3/10 11. 6/7 x 7/18 =42/126

That's multiplying proper fractions. This is how you multilying Mixed fractions and improper Question 4.

That's when you ever have a improper fraction and you get the anwer right you have mixed fraction.

4.

Dividing fraction and Mixed numbers

and I don't get with number two 3/4 divide 1/2 :?

### Monica's Growing Post

Me Nadine and Danielle, doing surface area questions.

top

lxw

12x4.5

54x2

=108

side

lxw

10.4x4.5

46.8x2

=93.6

front

lxw

12x10.4

124.8x2

=249.6

TSA:108+93.6+249=451.6 cm2

bxh/2

8x7/2

56/2

=28

lxw

10.6x2.5

=26.5

lxw

2.5x7

=17.5

lxw

8x2.5

=20

tsa: 28+28+26.5+17.5+20=120cm2

r=d/2
r=9.5/2
r=4.75

2*3.14*r*r
2x3.14x4.75x4.75
=141.70

3.14xdxh
3.14x9.5x11
=328.13

tsa:140.70+328.13= 469.82 m2

## Sunday, March 21, 2010

### Jusitn's Surface Area Growing Post

TSA of rectangular prism

The rectangular prism has rectangular faces.

So, use the formula A = lw to find the area of the faces.

For both the front and back faces, l = 5 in. and w = 2 in.

So, the area of the front and back faces is,

5 2 2 = 20 in.2

For both the top and bottom faces, l = 14 in. and w = 5 in.

So, the area of the top and bottom faces is,

14 5 2 = 140 in.2

For both the sides, l = 14 in. and w = 2 in.

So, the area of the two sides is,

14 2 2 = 56 in.2

Add the area of the faces.

20 + 140 + 56 = 216

So, the total surface area of the given solid is 216 in.2.

TSA of triangular prism

The triangular prism has triangular bases.

So, to find the area of the bases, use the formula:

Substitute 6 for b and 8 for h.

Therefore, the area of the two bases is,

2(24) = 48 cm2

The triangular prism has rectangular sides.

So, use the formula A = lw to find the area of the sides.

The area of the front side is,

13 8 = 104 cm2

The area of the bottom side is,

13 10 = 130 cm2

The area of the back side is,

13 6 = 78 cm2

Find the sum of the base areas and the area of the sides.

48 + 104 + 130 + 78 = 360

So, the total surface area of the given solid is 360 cm2.

TSA of a cylinder

The radius of the circular base is,

he area of a circle is, A = πr2 where r is the radius.

Replace π with 3.14, r with 2.4.

A (3.14)(2.4)2

A = 18.0864

So, the area of one base is 18.0864 cm2.

The sum of the areas of the two bases is,

18.0864 + 18.0864 = 36.1728 cm2

This video is on how to find the tsa of a cylinder , rectangular prism, and triangular prism. It was created by Warren, Bruce and I.