Saturday, March 10, 2012

Angela's Surface Area and Volume Post

*click on the images to enlarge*

How to find the Total Surface Area of a Rectangular Prism:



Method 1:

Step 1
: Find the areas of all the rectangles, FRONT, SIDE, and TOP.

  • Finding the area of the TOP rectangle:
Dimensions:
l = 5m
w = 10 m

l x w = area
5 x 10 = area
50m2 = area

  • Finding the area of the FRONT rectangle:
Dimensions:
l = 6m
w= 10m

l x w = area
6 x 10 = area
60m2 = area

  • Finding the area of the SIDE rectangle:
Dimensions:
l = 6m
w= 5m

l x w = area
6 x 5 = area
30m2 = area

Step 2: After you've found the area of the three rectangles you add them all up together:

50m2+60m2+30m2= 140m2

Step 3: After you've added all three sides you need to multiply the answer by 2:

140m2x 2 =SA
280m2 = SA

METHOD 2:
Step 1: Draw the NET of the rectangular Prism.

Step 2: Find the Area of the Lateral area:
To do this you need to....
Find the length by adding up the lengths of the rectangles:
6 + 5 + 6 + 5 = 22 m
l x w = LA
22 x 10 = LA
220m2= LA

Step 3: Find the area of the other 2 identical rectangles:
l x w = a
6 x 5 = a
30m2= a


Step 4: Add up all the areas:
SA= LA+2(l x w)
SA= 220+2(5 x 6)
SA= 220+2(30)
SA= 220+60
SA=280m2



How to find the Total Surface Area of Triangular Prisms:
























































How to find the Total Surface Area of Cylinder:


Here are some links that will help you get more practice:
Here's also a video:



Don't forget to play the new Manga High Challenges!:
Fun Math Games only at Mangahigh.com


Finding the Volume of a Rectangular Prism:


Finding the Volume of a Cylinder:






Finding the Volume of a Triangular Prism:



Here are some games that will enable you onto practicing on finding the volume of a shape:

2 comments:

  1. How simple do you think you can solve "A small terrace at a football ground comprises of 15 steps each of which is 50 m long and built of solid concrete. Each step has a rise of 1/4 m and a tread of 1/2 m. Calculate the total volume of concrete required to build the terrace. http://youtu.be/w8YLSavbgNM

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  2. Mensuration is a very important topic of mathematics as it is very much related to our daily life like area and volume of different solid figures or area of plot,length and breadth of different object.It is interlinked with many real life problems.
    icse textbooks for class 12

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