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    (Original post by NothingButWaleed)
    What does tagging do?
    It just means that you received a notification that directed you to this thread.
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    (Original post by notnek)
    It just means that you received a notification that directed you to this thread.
    oh ok
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    (Original post by NothingButWaleed)
    If half the machines are used it would take double the time to make all the bottles, hence, 4 machines would take 10 days!
    That's right. But you are told that the 4 machines worked for 2 days so they can't have made all the bottles. How much of the bottles did they make?
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    (Original post by NothingButWaleed)
    If half the machines are used it would take double the time to make all the bottles, hence, 4 machines would take 10 days!
    That would be the case if only 4 machines were in operation for the entirety of the time that it takes for the bottles to be manufactured.

    However,

    From the 3rd day, all 8 machines are used to make the bottles.
    How can you use your deduction that 8 machines take half as long as 4 machines to create the same amount of bottles?
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    (Original post by notnek)
    That's right. But you are told that the 4 machines worked for 2 days so they can't have made all the bottles. How much of the bottles did they make?
    i dont know
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    (Original post by _gcx)
    That would be the case if only 4 machines were in operation for the entirety of the time that it takes for the bottles to be manufactured.

    However,



    How can you use your deduction that 8 machines take half as long as 4 machines to create the same amount of bottles?
    What does "deduction" mean?
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    (Original post by NothingButWaleed)
    i dont know
    Ignore what I said. _gcx will help you solve the question in a better way.
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    (Original post by notnek)
    Ignore what I said. _gcx will help you solve the question in a better way.
    But i dont understand what he is talking about!
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    (Original post by _gcx)
    That would be the case if only 4 machines were in operation for the entirety of the time that it takes for the bottles to be manufactured.

    However,



    How can you use your deduction that 8 machines take half as long as 4 machines to create the same amount of bottles?
    Maybe multiply it by 2?
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    (Original post by NothingButWaleed)
    i dont know
    We know that 1 day with 8 machines will produce the same amount of bottles as 2 days with 4 machines. How can we use this information to work out how long it takes running with 4 machines for 2 days, then 8 machines after that?
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    (Original post by NothingButWaleed)
    But i dont understand what he is talking about!
    This is a tough question that most found hard - you just need a bit more explanantion and I think you'll get it, you just need to be patient! I can help later if _gcx isn't free.
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    (Original post by _gcx)
    We know that 1 day with 8 machines will produce the same amount of bottles as 2 days with 4 machines. How can we use this information to work out how long it takes running with 4 machines for 2 days, then 8 machines after that?
    I would use ratios...

    1 day :8 machines = same amount of bottles
    2 days:4 machines = same amount of bottles

    So..
    4 days:2 machines = same amount of bottles
    ?????
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    (Original post by NothingButWaleed)
    I would use ratios...

    1 day :8 machines = same amount of bottles
    2 days:4 machines = same amount of bottles

    So..
    4 days:2 machines = same amount of bottles
    ?????
    This might be a better way to think about it: Think of the 5 days as a countdown.

    Every day at half efficiency (4 machines) subtracts half (for essentially a half day's work).

    Every day at full efficiency (8 machines) subtracts one (for a full day's work)
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    (Original post by _gcx)
    this might be a better way to think about it: Think of the 5 days as a countdown.

    Every day at half efficiency (4 machines) subtracts half (for essentially a half day's work).

    Every day at full efficiency (8 machines) subtracts one (for a full day's work)
    whaaatttt???
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    (Original post by NothingButWaleed)
    I would use ratios...

    1 day :8 machines = same amount of bottles
    2 days:4 machines = same amount of bottles

    So..
    4 days:2 machines = same amount of bottles
    ?????
    Do you agree that 4 machines in 2 days make the same amount of bottles as 8 machines in 1 day?

    So if you like we can replace "4 machines in 2 days" to "8 machines in 1 day" in the question. So the question becomes:

    The 8 machines in the factory could make all the bottles in 5 days.
    All the machines work at the same rate.

    Stage 1 : For 1 day, 8 machines are used to make the bottles.
    Stage 2: All 8 machines are used to make the bottles.

    How long wil stage 2 take?
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    (Original post by notnek)
    Do you agree that 4 machines in 2 days make the same amount of bottles as 8 machines in 1 day?

    So if you like we can replace "4 machines in 2 days" to "8 machines in 1 day" in the question. So the question becomes:

    The 8 machines in the factory could make all the bottles in 5 days.
    All the machines work at the same rate.

    Stage 1 : For 1 day, 8 machines are used to make the bottles.
    Stage 2: All 8 machines are used to make the bottles.

    How long wil stage 2 take?
    5 days
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    (Original post by notnek)
    Do you agree that 4 machines in 2 days make the same amount of bottles as 8 machines in 1 day?

    So if you like we can replace "4 machines in 2 days" to "8 machines in 1 day" in the question. So the question becomes:

    The 8 machines in the factory could make all the bottles in 5 days.
    All the machines work at the same rate.

    Stage 1 : For 1 day, 8 machines are used to make the bottles.
    Stage 2: All 8 machines are used to make the bottles.

    How long wil stage 2 take?
    OHHHHHHHHHHH.....
    so 1 day for 8 bottles and 5 days for the rest so 1+5 = 6 days in total!
    This is such a good way to understand it the other ways were so confusing
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    (Original post by NothingButWaleed)
    5 days
    No, notice that stage 1 took 1 day and 8 machines make all the bottles in 5 days. So how many extra days are needed for stage 2?
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    (Original post by NothingButWaleed)
    OHHHHHHHHHHH.....
    so 1 day for 8 bottles and 5 days for the rest so 1+5 = 6 days in total!
    This is such a good way to understand it the other ways were so confusing
    No this isn't right but you're close. Read my post above.

    Also remember that "1 day for 8 bottles" is used as a technique to find the number of days in stage 2. But stage 1 actually took 2 days if you read the question.
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    (Original post by notnek)
    No, notice that stage 1 took 1 day and 8 machines make all the bottles in 5 days. So how many extra days are needed for stage 2?
    idk how can i work that out?
 
 
 
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