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How many liters of paint

  1. Sep 2, 2005 #1
    Please help (wrote the question wrong) please help

    Me and my friend have this question we were asked and we dont know it but if you have 100 blocks by 100 blocks 97cm wide 97cm deep 93 cm tall.

    1 liter of paint covers 3 square meters how many liters of paint would you need rounded up.

    Please help and thanks
    Last edited: Sep 2, 2005
  2. jcsd
  3. Sep 2, 2005 #2
    Assuming the measurements referr to the individual blocks, they each have 4 sides that are 97*97 and 2 that are 97*93. Hence each block is 55678 cm^2 and need 18559 1/3 liter of paint. You have ten thousand, so multiply that in too. You'll end up needing about 185.5 million liters (~49 million US gallon, roughly the total US house paint production during the past two months, btw. Hey, perhaps I should write pop science..).

    While it's got to be some pretty strange paint to only cover 3 cm^2/l (~1.76 square inches per gallon. A gallon wouldn't be enough to paint the front and back of a postage stamp), that be the numbers..
  4. Sep 12, 2005 #3


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    3 square meters.
  5. Sep 12, 2005 #4


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    You have an array of blocks: 100x100, correct? That's a total of 10,000 blocks.

    You want all six sides of each block painted? You don't specify.

    Presuming you do, each block will have a surface area of
    2x 97x97 + 4x 97x93 cm^2.
    Now multiply that by the number of blocks: x10,000 - which equals your total surface area in cm^2 - then convert it to m^2 (i.e. coincidentally, dividing by 10,000).

    You now know the total area to bre covered, in m^2, and you know 1 litre covers 3 m^2. How many litres will you need?
  6. Sep 12, 2005 #5
    It was originally 1l/cm^2, the post has since been edited (with good reason) to reflect the actual problem (personally I usually put littled [EDIT] notes at the bottom explaining potential changes to avoid just this sort of problem, that way it's more obvious what was changed and why later posts don't necessarily reflect the new content). I was told this in a PM but since it smelled a bit of homework in my book I just went over the methods.
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