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  1. #1
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    Wink Problem

    Hi everybody,

    I'm French and I had my first mathematic class today.

    I don't understand an exercise :

    Can you help me ?

    A brother and sister share out their collection of 5.000 stamps in the ration 5:3.
    The brother then shares his stamps with his 2 friends in the ratio 3:1:1, keeping more for himself.
    How many stamps do each of his friends receive ?

    Thx a lot
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  2. #2
    Member Traveller's Avatar
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    It means that if the brother has 5x stamps for some x, then the sister has 3x stamps.

    After the brother shares his stamps with his friends, if the brother has 3y stamps for some y, then both of his friends have y stamps each. You have to find y.
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  3. #3
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    Hello, FreeRiderZ!

    A brother and sister share out their collection of 5.000 stamps in the ration 5:3.

    The brother then shares his stamps with two friends in the ratio 3:1:1,
    keeping more for himself.

    How many stamps do each of his friends receive ?

    $\displaystyle \begin{array}{cccccc}
    \text{The brother got }5a\text{ stamps} \\
    \text{The sister got }3a\text{ stamps} \end{array}\;\text{ for some integer } a.$

    There were 5,000 stamps: .$\displaystyle 5a + 3a \:=\:5000$

    . . $\displaystyle 8a \:=\:5000 \quad\Rightarrow\quad a \:=\:625$


    $\displaystyle \begin{array}{cccccc}\text{The brother got: }& 5a &=& 5(625) &=& 3125\text{ stamps.} \\
    \text{The sister got: }& 3a &=& 3(625) &=& 1875\text{ stamps.} \end{array}$


    The brother divided his stamps into three groups: .$\displaystyle 3b,\:b,\;b$

    We have: .$\displaystyle 3b + b + b \:=\:3125 \qiad\Rightarrow\quad 5b \:=\:3125 \quad\Rightarrow\quad b \:=\:625$


    He gave his two friends 625 stamps each.

    . . . (And kept 1875 stamps for himself.)
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