Page 1 of 2 12 LastLast
Results 1 to 15 of 18

Math Help - Problem set: inequalities, ratios, basic algebra

  1. #1
    Newbie
    Joined
    Oct 2010
    Posts
    9

    Red face Problem set: inequalities, ratios, basic algebra

    i need the answers to:
    1. Write the following inequality as interval notation 2 < x ≤ 5
    2. The ratio of two numbers is 7:2 The two numbers add up to 90 find the two numbers.
    3. Twenty less than a number is 56
    4. i am thinking of a number such that 6 less than the product of 7 and this number is 85
    5. A classroom contained an equal of number of boys and girls. Eight girls left to play hockey, leaving twice as many boys as girls in the classroom. what was the original number of students present.
    Thanks please show work guys please
    Follow Math Help Forum on Facebook and Google+

  2. #2
    is up to his old tricks again! Jhevon's Avatar
    Joined
    Feb 2007
    From
    New York, USA
    Posts
    11,663
    Thanks
    3
    Quote Originally Posted by Bijou View Post
    ...please show work guys please
    that's our line!

    i'm sorry, this is not a homework or answer service. we don't just give out answers. we help you to get to them yourself. please show your work and explain where you got stuck or what you don't understand

    this smells like you want us to do your homework, which is not good, and against MHF policy.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Oct 2010
    Posts
    9
    ok can you help me
    Follow Math Help Forum on Facebook and Google+

  4. #4
    is up to his old tricks again! Jhevon's Avatar
    Joined
    Feb 2007
    From
    New York, USA
    Posts
    11,663
    Thanks
    3
    Quote Originally Posted by Bijou View Post
    ok can you help me
    um...you didn't do anything.

    show your work for each problem and explain where you are stuck or what you don't understand...
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Newbie
    Joined
    Oct 2010
    Posts
    9
    im i dont understand any of them so can we start at number 1
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by Bijou View Post
    im i dont understand any of them so can we start at number 1
    In that case, doing them for you is not going to help you understand them. You need to go back to your class notes of textbook and review the material. Then you need to arrange one-on-one help from your teacher or some other love instructor.

    Here is #1, for what it's worth: (2, 5].
    Follow Math Help Forum on Facebook and Google+

  7. #7
    Member
    Joined
    Sep 2010
    Posts
    149
    Thanks
    3
    for #2, the question gives you two pieces of information:
    (1) x/y = 7/2
    (2) x +y = 90
    can you solve them now using simultaneous equations?

    for #3,
    x - 20 = 56 , solve for x

    for #4,
    7x - 6 = 85 , solve for x

    do you think you could do #5 by yourself now? It seems as though you are having trouble understanding what the actual questions are asking, you should definitely ask your teacher for some help.
    Follow Math Help Forum on Facebook and Google+

  8. #8
    Newbie
    Joined
    Oct 2010
    Posts
    9
    thanks but i really dont get 5 i got 16 as a answer which is wrong im stuck?
    Follow Math Help Forum on Facebook and Google+

  9. #9
    Newbie
    Joined
    Oct 2010
    Posts
    9
    can you explain question #2 much better thanks
    Follow Math Help Forum on Facebook and Google+

  10. #10
    Member
    Joined
    Sep 2010
    Posts
    149
    Thanks
    3
    for #2..
    let x and y be the two numbers you are looking for.
    when it says the ratio of the two number is 7:2, it means x:y = 7:2.. this is the same as saying x/y = 7/2
    if you multiply both sides of that equation by y,
    you get x = (7y)/2

    you are also given x + y = 90
    now you sub in x = (7y)/2 into x + y = 90 and see what you get

    in #5, you are also given two pieces of information.
    if we let g=# of girls, b=# of boys, we have

    initially, g=b and when 8 girls leave, g-8 = b/2
    Can you use these pieces of information to work it out? Remember you are trying to find the original number of students present (boys + girls)
    Follow Math Help Forum on Facebook and Google+

  11. #11
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by Bijou View Post
    thanks but i really dont get 5 i got 16 as a answer which is wrong im stuck?
    You have calculated the number of boys (which is also the same as the number of girls) .... (One of the reasons why you should always write down the definition of any pronumeral you use at the very start of your solution).
    Follow Math Help Forum on Facebook and Google+

  12. #12
    Newbie
    Joined
    Oct 2010
    Posts
    9
    for #5 i got 4 as a answer 16 -8=8 then 8 divided by 2 = 4 right or wrong?
    Follow Math Help Forum on Facebook and Google+

  13. #13
    MHF Contributor

    Joined
    Apr 2005
    Posts
    14,974
    Thanks
    1121
    Quote Originally Posted by Bijou View Post
    for #5 i got 4 as a answer 16 -8=8 then 8 divided by 2 = 4 right or wrong?
    You got 4 as an answer? Does that even make sense to you?

    The question asked "What was the original number of students?" and you were told "8 girls left".


    If there were only 4 students originally, how could 8 girls have left?

    THINK!
    Follow Math Help Forum on Facebook and Google+

  14. #14
    Newbie
    Joined
    Oct 2010
    Posts
    9
    can you go over it step by step with me please you ask questions i answer until i get the answer
    Follow Math Help Forum on Facebook and Google+

  15. #15
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by Bijou View Post
    can you go over it step by step with me please you ask questions i answer until i get the answer
    You found that the number of boys was equal to 16. And you're told "A classroom contained an equal of number of boys and girls". Think!
    Follow Math Help Forum on Facebook and Google+

Page 1 of 2 12 LastLast

Similar Math Help Forum Discussions

  1. Replies: 3
    Last Post: September 29th 2011, 06:33 AM
  2. Basic Trig Ratios - Circles, Tangents and Triangles
    Posted in the Trigonometry Forum
    Replies: 3
    Last Post: March 8th 2011, 04:52 PM
  3. Basic Linear Algebra Problem
    Posted in the Advanced Algebra Forum
    Replies: 6
    Last Post: January 14th 2011, 11:20 AM
  4. Replies: 1
    Last Post: January 28th 2010, 11:21 AM
  5. need help with basic algebra problem
    Posted in the Algebra Forum
    Replies: 2
    Last Post: February 19th 2009, 09:10 PM

Search Tags


/mathhelpforum @mathhelpforum