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Math Help - word problem

  1. #1
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    word problem

    I can't figure out how to write this problem out, so that I can solve it. Here it is: Three times a certain number is as much less than 55 as 4 times the number exceeds 50. What is the number? Can someone help me please? Thanks.
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  2. #2
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    Quote Originally Posted by jesuslover View Post
    I can't figure out how to write this problem out, so that I can solve it. Here it is: Three times a certain number is as much less than 55 as 4 times the number exceeds 50. What is the number? Can someone help me please? Thanks.
    What does "as much less than" mean? Perhaps, if you reworded your problem, then we can answer you. This is the best I could come up with:

    55-3x = 4x-50

    x = \frac{105}{7} \Rightarrow x = 15
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  3. #3
    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by jesuslover View Post
    I can't figure out how to write this problem out, so that I can solve it. Here it is: Three times a certain number is as much less than 55 as 4 times the number exceeds 50. What is the number? Can someone help me please? Thanks.
    Let the number be x

    then the amount that three times the number is less than 55 is: 55 - 3x

    and the amount that 4 times the number exceeds 50 is: 4x - 50

    we are told these are the same, that is: 55 - 3x = 4x - 50

    now solve for x

    EDIT: Ah, Colby beat me to it and did it for you
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  4. #4
    Senior Member DivideBy0's Avatar
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    Quote Originally Posted by jesuslover View Post
    I can't figure out how to write this problem out, so that I can solve it. Here it is: Three times a certain number is as much less than 55 as 4 times the number exceeds 50. What is the number? Can someone help me please? Thanks.
    It's also interesting to note that you could interpret the 'amount less' or the 'amount exceeding' as negative values \Rightarrow 3x>55 and 50>4x so you get

    3x-55=50-4x

    But this still gets you to x = 15

    Note that you cannot allow the 'amount 3x is less than 55' and the 'amount 4x exceeds 55' to alternate in sign, as this would lead to the incorrect equations:

    3x-55=4x-50 or 55-3x=50-4x

    As the LHS's sign is not equal to the RHS's sign, this cannot be possible.
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  5. #5
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    Hello, jesuslover!

    Sometimes, "baby talk" will help . . .


    Three times a certain number is as much less than 55
    as 4 times the number exceeds 50.
    What is the number?

    Let x = the number.

    "Three times x is as much less than 55" tells us that 3x is less than 55.
    How much less?
    . . The difference is: . 55-3x

    "Four times number exceeds 50" tells us that 4x is greater than 50.
    How much more?
    . . The amount is: . 4x - 50

    We are told that these amounts are equal.

    . . There is our equation! . 55-3x \:=\:4x-50


    Go for it!

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  6. #6
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    Thank-you. I had 3n-55 =4n+50, which didn't come out right. I see where I messed up. Thanks a lot.
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  7. #7
    is up to his old tricks again! Jhevon's Avatar
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    man, we're really beating this problem to death aren't we?
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  8. #8
    Senior Member DivideBy0's Avatar
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    Quote Originally Posted by Jhevon View Post
    man, we're really beating this problem to death aren't we?
    It seems that it's a race to get to every question first.
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