Height of Each Brother

Discussion in 'Algebra' started by nycmathguy, Dec 2, 2021.

  1. nycmathguy

    nycmathguy

    Joined:
    Jun 27, 2021
    Messages:
    5,386
    Likes Received:
    422
    Next door to me live four brothers of different heights. Their average height is 74 inches, and the difference in height among the first three men is two inches. The difference between the third and fourth men is six inches. Can you tell how tall is each brother?

    Let me see.

    There are 4 brothers.
    Each brother is about 74 inches tall.

    Let x = age of each brother.

    Here's where I got lost:

    ". . .the difference in height among the first three men is two inches. The difference between the third and fourth men is six inches."

    How is the quote above translated into algebra?

    Stuck....
     
    nycmathguy, Dec 2, 2021
    #1
  2. nycmathguy

    MathLover1

    Joined:
    Jun 27, 2021
    Messages:
    2,989
    Likes Received:
    2,884
    Let 1st be a, 2nd be b, 3rd be c & 4th be d

    given that the difference in height among the first three men is 2 inches, so

    a = a
    b = a+2
    c = b+2 = a+2+2=a+4
    The difference between the third and fourth men is 6 inches
    d = c+6 = a+4+6=a+10

    Thus, the average is
    74=(a +b +c +d)/4...............substitute b, c, and d

    74=(a+a+2+a+4+a+10)/4

    74=(4a+16)/4

    74=a+4

    a=70

    Thus,

    b = a+2 = 70+2 = 72

    c = a+4 = 70+4 = 74

    d = a+10 = 70+10 = 80

    the height of 4 brothers are as follow:

    1st - 70 Inches

    2nd - 72 inches

    3rd - 74 inches

    4th - 80 inches

     
    MathLover1, Dec 2, 2021
    #2
    nycmathguy likes this.
  3. nycmathguy

    nycmathguy

    Joined:
    Jun 27, 2021
    Messages:
    5,386
    Likes Received:
    422
    I give up. I could never reason my way through the problem as you did. Feeling frustrated. Ha!
     
    nycmathguy, Dec 2, 2021
    #3
  4. nycmathguy

    Country Boy

    Joined:
    Dec 15, 2021
    Messages:
    157
    Likes Received:
    38
    I would say that "the difference in height among the first three men is two inches" is ambiguous. It could mean that B is two inches taller than A and C is two inches taller than B (so four inches taller than A) of it could mean that the tallest of the the three men is two inches taller than the shortest with the third somewhere in between.

    Of course, in order to be able to solve this problem you have to assume the first as you did so I am just nit-picking.
     
    Country Boy, Dec 29, 2021
    #4
    nycmathguy likes this.
  5. nycmathguy

    nycmathguy

    Joined:
    Jun 27, 2021
    Messages:
    5,386
    Likes Received:
    422
    If the question is unclear to you, think how totally unclear it is to me.
     
    nycmathguy, Dec 30, 2021
    #5
  6. nycmathguy

    Country Boy

    Joined:
    Dec 15, 2021
    Messages:
    157
    Likes Received:
    38
    I did not say it was "unclear", I said it was "ambiguous". Those are not the same!
     
    Country Boy, Jan 19, 2022
    #6
  7. nycmathguy

    nycmathguy

    Joined:
    Jun 27, 2021
    Messages:
    5,386
    Likes Received:
    422
    Ambiguous or whatever the word, the problem is unclear to me.
     
    nycmathguy, Jan 20, 2022
    #7
  8. nycmathguy

    MathLover1

    Joined:
    Jun 27, 2021
    Messages:
    2,989
    Likes Received:
    2,884

    am·big·u·ous
    /amˈbiɡyo͞oəs/
    Learn to pronounce

    adjective
    1. (of language) open to more than one interpretation; having a double meaning.
      "ambiguous phrases"
      • unclear or inexact because a choice between alternatives has not been made.
        "the election result was ambiguous"
    practically same :)
     
    MathLover1, Jan 20, 2022
    #8
    nycmathguy likes this.
  9. nycmathguy

    nycmathguy

    Joined:
    Jun 27, 2021
    Messages:
    5,386
    Likes Received:
    422
    Exactly. Almost the same in meaning. By the way, I have put aside math during the week. Dealing with a lot of stuff back home, as you could well imagine.

    A. My roommate has become abusive. Not helping me with bills, stealing my food, using my toilet paper, bounty paper towels, etc.

    B. Still no heat in my room in the middle of winter. The house owner has been putting aside calling a professional heating company to fix the problem. The radiator is broken.

    Sorry. . .this is a math forum.
     
    nycmathguy, Jan 21, 2022
    #9
  10. nycmathguy

    MathLover1

    Joined:
    Jun 27, 2021
    Messages:
    2,989
    Likes Received:
    2,884
    if he house owner has been putting aside calling a professional heating company to fix the problem, you have right to move somewhere else
     
    MathLover1, Jan 21, 2022
    #10
    nycmathguy likes this.
  11. nycmathguy

    nycmathguy

    Joined:
    Jun 27, 2021
    Messages:
    5,386
    Likes Received:
    422
    I am looking for a room as I type this to you.
     
    nycmathguy, Jan 21, 2022
    #11
Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Similar Threads
There are no similar threads yet.
Loading...