Results 1 to 6 of 6

Math Help - volumes of cylinders

  1. #1
    Junior Member
    Joined
    Aug 2010
    Posts
    49

    volumes of cylinders

    a right circular cylinder has a diameter of 5.7 inches and a height of 6.4 feet
    a.) what is the volume of the cylinder in ft^3?
    b.) what is the volume of the cylinder in cubic metres?
    c.)what is the volume of the cylinder in litres?

    so for ft^3 i knew that
    the volume of a cylinder is (pi)r^2*h
    so i did 2.85in.^2 * 6.4ft
    v= 51.984 ft^3 is this correct?
    and how do i do the other ones?^
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member
    Joined
    Nov 2007
    From
    Trumbull Ct
    Posts
    908
    Thanks
    27

    volume of cylinders

    Hi gabriel,
    You have the right formula but units must be consistent. R must be converted to feet and volume will then be in cubic ft . So what must you do to get results in cubic meters or in liters.You also can use the diameter directly by using a revised formula. pi d^2 /4 for area. Look up conversion factors.



    bjh
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Aug 2010
    Posts
    49
    so is the answer 1.134 cubic inches?
    i found out that r=2.85 in so r=.2375 feet
    so (pi)(2.375ft)^2(6.4 feet)
    v=1.134 ft^3
    ^correct?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Super Member
    Joined
    Nov 2007
    From
    Trumbull Ct
    Posts
    908
    Thanks
    27
    Hi again gabriel,
    Your answer to question 1 is correct but you made a decimal error in your calculation. How about doing 2 and 3?


    bjh
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Junior Member
    Joined
    Aug 2010
    Posts
    49
    ok so for 2 i got 0.1054 m^3
    and for 3 i got 7.19 x 10^-3 litres
    1 liter= 0.03531 ft ^3
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Super Member
    Joined
    Nov 2007
    From
    Trumbull Ct
    Posts
    908
    Thanks
    27
    Hi gabriel,

    If you showed your work I could tell you where you went wrong. Both answers for questions for 2 and 3 are wrong. 1 liter is 0.03531 cu ft as you show so the reciprocal equals = 28.32 which is the number of liters in a cu ft


    bjh
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Intersection of Three cylinders
    Posted in the Calculus Forum
    Replies: 1
    Last Post: November 16th 2011, 05:21 PM
  2. Replies: 6
    Last Post: February 11th 2010, 07:08 PM
  3. About cylinders
    Posted in the Calculus Forum
    Replies: 0
    Last Post: September 6th 2008, 06:43 PM
  4. optimizing - cylinders
    Posted in the Calculus Forum
    Replies: 1
    Last Post: December 2nd 2006, 11:53 PM
  5. Cylinders
    Posted in the Calculus Forum
    Replies: 1
    Last Post: December 2nd 2006, 10:45 PM

Search Tags


/mathhelpforum @mathhelpforum