Math question regarding Volume of a cylinder

Discussion in 'Chit Chat' started by tango29, Sep 28, 2020.

  1. tango29

    tango29

    Given V = h(pi)r^3 and the radius is 10 times the height
    so as given in book: V = 1/10(pi)r^3...that is exactly as it shows, in case of question
    What is the volume with radius =9
    Big argument at home at the moment over this one.
    The youngest doing it has the wrong answer according to the book, the middle son has a different answer than me, and none of us is willing to concede the other is right.
     
  2. newwurldmn

    newwurldmn

    isn't volume h*pi*r^2?

    you take the surface area of the circle and multply it by the height
     
    vanzandt likes this.
  3. newwurldmn

    newwurldmn

    pi*r^3 i think is volume of a sphere.
     
  4. tango29

    tango29

    Just repeating what the problem is as given in the book, online book, but you are absolutely correct! So I guess try solving as given even if it is wrong as given. This is a Wiley online textbook, and since the beginning of the semester this the 3rd item that was incorrect as given by them. The last time my youngest asked about one of the errors his TA was ticked and mentioned he is running into errors constantly from their online books.
     
  5. tango29

    tango29

    Also, thank you for the catch!
     
  6. Remember the ole Cajun cook, Justin Wilson? Told the story of his son coming home from college and Justin asked him "What you learn at college, boy, tell me something you done learnt." His son said "Pi r square." Justin said "What you say, boy?" "Pi r square." Justin smacked him on his head and said "Why I send you to that fancy school, and they don't teach you nuthin'." "Pie are round, cornbread are square!"
     
  7. mlawson71

    mlawson71

    I was looking at the formula and thinking "Waaaiiit, this is not how you calculate the volume of a cylinder", then I noticed the other comments. It's very annoying when textbooks have issues like that.
     
  8. tango29

    tango29

    Yes it is, and have hit a couple more since my first question. I have a feeling the TA, who gets all the questions about issues, is probably thinking he is done with this TA job.
     
  9. Wallet

    Wallet

    My favorite was his story about the elderly couple who purchased a mirror from the traveling salesman. The husband was surprised he had found a picture of his old papa. The husband hid it in the barn because he had taken the wives egg money to pay for it. The wife found the mirror in the barn and thought it was a picture of the woman the husband had been seeing on the side.
     
  10. Am I supposed to remember the answer to this after all these years of being out of school?

    No way Jose. :banghead:
     
    #10     Oct 9, 2020