Results 1 to 2 of 2

Math Help - Is my book answer incorrect?

  1. #1
    Newbie
    Joined
    Apr 2009
    Posts
    5

    Question Is my book answer incorrect?

    Hi,

    I have a simple Volume problem that I would like some assistance with please: I have a Cylinder of Duct work measuring 6' long and 6" (diameter) or height. I need the Volume of aire inside it so I am using the following formula:  V = pi r^2 h
    V = (3.141592)(3in)^2 (72in)
    V = (3.141592)(9in)(72in)
    V = (3.141592)(648)
    V = 2035.75"^2

    Now my book has an answer of  1.2^3 feet.

    What in the world am I doing wrong?

    I am so confused here. If only the book would give more than just an answer...

    TIA,
    GA
    Follow Math Help Forum on Facebook and Google+

  2. #2
    A riddle wrapped in an enigma
    masters's Avatar
    Joined
    Jan 2008
    From
    Big Stone Gap, Virginia
    Posts
    2,551
    Thanks
    12
    Awards
    1
    Quote Originally Posted by garms View Post
    Hi,

    I have a simple Volume problem that I would like some assistance with please: I have a Cylinder of Duct work measuring 6' long and 6" (diameter) or height. I need the Volume of aire inside it so I am using the following formula:  V = pi r^2 h
    V = (3.141592)(3in)^2 (72in)
    V = (3.141592)(9in)(72in)
    V = (3.141592)(648)
    V = 2035.75"^2

    Now my book has an answer of  1.2^3 feet.

    What in the world am I doing wrong?

    I am so confused here. If only the book would give more than just an answer...

    TIA,
    GA
    Hi garms,

    You converted your units to inches, so the result came out in inches cubed.

    To covert back to feet cubed, you will need to divide by 12 cubed (1728) because that's how many cubic inches there are in 1 cubic foot.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 1
    Last Post: October 4th 2010, 05:46 PM
  2. Answer in the back of the book wrong?
    Posted in the Statistics Forum
    Replies: 1
    Last Post: October 4th 2009, 09:43 PM
  3. Replies: 4
    Last Post: November 15th 2008, 02:23 AM
  4. My answer doesn't match the book
    Posted in the Algebra Forum
    Replies: 2
    Last Post: June 20th 2008, 07:30 AM
  5. Replies: 2
    Last Post: December 18th 2006, 08:20 AM

Search Tags


/mathhelpforum @mathhelpforum