Tuesday, April 18, 2006

Volume and Surface Area Questions

1.How much cement is needed to build a sidewalk that is one thousand, one hundred twenty metres long, four metres wide and fifty centimetres thick? Round your answer to the nearest cubic metre.

Ok..first of all you check the measurement and the type of measurement .. in this case it's metre..don't forget that!

Basically in this case you just need to multiply all the numbers together....

1120 X 4 X .5

btw... its .5 because in the question it says 50 CM not M so i must divide by 100.... 50/100 = .5

anyways: 1120 X 4 X .5 = 1125

but because a rectangular prism has 6 sides all together...we must multiply this by 2...

1125(2)= 2250 is the answer to this world problem

remember..... METRES is the type of measurement!

so it is: 2250 m3

-------------------------------------------------------------------------------------------------------------------------------------------------------------------------

3. If you have five 5 cm by 5 cm x 5 cm aluminum cubes and superglue them together in a row, what is the surface area of the resulting shape made by the five cubes?

I must remember the fact that they are all IN A ROW and so its not just the normal thing like...5X5= 25 (2) and so on....

It should be something like: 5 X 25 = 125 (2) = 250
: 5 X 5 = 25 (2) = 50
: 5 X 25 = 125 (2) = 250

add them all up equals: 550 cm2

i hope that's right!

-dandan =)




Français/French Deutsch/German Italiano/Italian Português/Portuguese Español/Spanish 日本語/Japanese 한국어/Korean 中文(简体)/Chinese Simplified Tagalog/Filipino

0 Comments:

Post a Comment

<< Home