## Monday, April 14, 2008

### Kevin's BOB

In this B.O.B. we are going to find out how
to find the volume and the surface area of
a rectangular prism.

What we did was draw a net of our shape out on gird paper and each cube represents 1 cm and then we labled it. Make sure the formula is writen down. The formula is ....

2 ( 4 x 2 )+ 2 ( 1 x 2 )+ 2 ( 4 x 1 ) =

2 (8 cm2 ) +2 ( 2 cm2 ) + 2 ( 4cm2 ) =

16 cm2 + 4cm2 + 8cm2 = 28 cm2

A secccond way is to just add the lengths together like this... 2cm 2 + 2cm2 + 4 cm2 + 4 cm2 + 8cm2 + 8 cm 2 = 28 cm2

To find the area of a rectangular prism you can use 2 diffrent stratigies or formulas. You can use...

( L x W ) x H = area or you can also use....... Area of the base x height. in this B.O.B we are going to solve it using both. First we drew a net of the rectangular prism.

Fromula : ( L x W ) x H = area

L = 8
W = 4 ( L x W ) x H
H = 1 ( 8 x 4 ) x 1 =

32 x 1 = 32 cm 3

The seccond way to solve this equation is to use the formula >>>>>> Area of the base x height = area of a rectangular prism.

The area of our base is 32 and 32 x our height would be 32 x 1= 32 cm 3. Since we are dealing with a 3 dimensional shape we have to make sure we use cubed witch is 3 instead of 2.

#### 1 comment:

judy817 said...

thanks! :) haha i like your post too! you made it simpler by just taking pictures! :P good job!