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Homework Help: A room is 25 ft long

  1. May 31, 2010 #1
    A room is 25 ft long , 20 ft wide and 15 ft tall . Express the volume of the room in cubic metres . [ 1m = 3.281ft]



    I sure my answer is wrong but I try



    Now we have 25 ft long , 20 ft wide and 15 we must change all this to cubic metres



    3.281ft = 1m



    25 X 3.281ft

    20 X 3.281ft

    15 X 3.281ft
     
  2. jcsd
  3. May 31, 2010 #2
    1 m = 3.281 ft
    x m = 25 ft

    Multiply it cross-like ;) and you get:
    25 ft * 1m = x m * 3.281 ft
    divide it by 3.281 ft and you get
    x m=(25 ft * 1m)/(3.281 ft)
     
  4. May 31, 2010 #3

    Mark44

    Staff: Mentor

    So 1 ft = (1/3.281)m.
    Yes, these are all wrong. Also, you are not paying attention to the units being used. Your first expression is 25 X 3.281 ft = 82.025 ft. This makes no sense. 25 feet is not equal to 82.025 feet.

    You need to convert each measurement in feet to the equivalent length in meters, then multiply all three together to get cubic meters.

    For the room length, 25 ft = 25 ft * (1/3.281) m/ft = ?? m. It should be about 8 m.

    Do the same for the other two room dimensions, then multiply all three together to get the volume.
     
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