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    A student possesses brandy containing 42%v/v ethanol and wine containing 10% ethanol. What volume of brandy should be diluted with the wine to produce 150ml of a cordial containing 15% ethanol? Report the answer to the nearest 1ml.

    How do I work this out?
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    Misread the question
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    (Original post by Ateo)
    What are the volumes of brandy and wine?
    It's not given.
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    (Original post by sultryabyss)
    It's not given.
    Oops, I interpreted the question incorrectly. You do this by ratios.

    Let V_1 be volume of brandy and V_2 be the volume of wine both in ml. Then:

    V_1 + V_2 = 150 (1)

    Also we want 15% concentration at the end, thus:

    42 \cdot \frac{V_1}{150} + 10 \cdot \frac{V_2}{150} = 15 (2)

    Solve (1) and (2) simultaneously.

    Why on earth would you dilute brandy?
 
 
 
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