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    I know this is simple, but it annoyed me, and I want to know if I've done it right or not, because the book doesn't tell you how you should have answered it.

    Question:

    The cost of an anorak rose by £6. As a result a shop could buy 5 fewer anoraks for £600. If the cost of an anorak was £x before the rise, find expressions in terms of x, for the number of anoraks which could be bought before and after the rise. Hence form an equation in x and show that it reduces to x^2 + 6x - 720. Solve this equation and state the original cost of the anorak.

    So I did this:

    Before rise: \frac {600}{x}
    After: \frac {600}{x} - 5 or \frac {600}{x+6}

    \frac {600}{x} - 5 = \frac {600}{x+6}

    Simplified to get 5x^2 + 30x - 3600

    Then divided it all by 5 to get what was asked. So the original price was
    £24.

    Is that how I was supposed to do it?
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    Looks right.
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    Or -30 pounds.
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    (Original post by Simplicity)
    Or -30 pounds.
    Wouldn't that be good?
    They give me £30 if I want an anorak.

    Would give me a reason to wear one xD
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    (Original post by Ben77mc)
    Wouldn't that be good?
    They give me £30 if I want an anorak.

    Would give me a reason to wear one xD
    Well, the math says it works so yeah, it must work.
 
 
 
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