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  1. #1
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    algebra word problem

    alice invested a portion of $500 at 4% interest and the remainder at 5%.
    how much did she invest at each rate if her total income from both investments is $23.28.
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  2. #2
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    Quote Originally Posted by watsod8 View Post
    alice invested a portion of $500 at 4% interest and the remainder at 5%.
    how much did she invest at each rate if her total income from both investments is $23.28.
    Let x = amout invested at 4%

    Let 500 - x = amount invested at 5%

    .04x + .05(500 - x) = 23.28

    Finish up....good luck.
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  3. #3
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    Quote Originally Posted by watsod8 View Post
    alice invested a portion of $500 at 4% interest and the remainder at 5%.
    how much did she invest at each rate if her total income from both investments is $23.28.
    Let x denote the amount which is invested at 4%, then (500-x) are invested at 5%:

    x \cdot \frac4{100} + (500-x) \cdot \frac5{100} = 23.38

    Solve for x. I've got $162
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  4. #4
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    Hi,

    I tried to solve this and I don't get $162 . can someone please check my working and tell me were I have gone wrong .

    thank you

     0.4x + 0.5(500-x) = 23.38

     0.4x + 250-0.5x = 23.38

     -0.1x + 250 = 23.38

     -0.1x = -226.62

     x = 2266.2

    ?
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  5. #5
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    Quote Originally Posted by earboth View Post
    Let x denote the amount which is invested at 4%, then (500-x) are invested at 5%:

    x \cdot \frac4{100} + (500-x) \cdot \frac5{100} = {\color{red}23.38}

    Solve for x. I've got $162
    Typo, Earboth, but setup is good. Investment at 4% = $172
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  6. #6
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    I don't get $172. were have I gone wrong?
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  7. #7
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    Quote Originally Posted by Tweety View Post
    Hi,

    I tried to solve this and I don't get $162 . can someone please check my working and tell me were I have gone wrong .

    thank you

     0.4x + 0.5(500-x) = 23.38

    First, it's 23.28, not 23.38

    Second, 4%=.04 and 5%=.05

     0.4x + 250-0.5x = 23.38

     -0.1x + 250 = 23.38

     -0.1x = -226.62

     x = 2266.2

    ?
    Corrections in red.
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