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Thread: Multiplication: What is the meaning of 2 apples * 5 people ?

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    Multiplication: What is the meaning of 2 apples * 5 people ?

    I know that 8 apples per 4 persons is = 2 apples per person.
    But What is the meaning of 2 apples * 5 people ?
    I got 10 applesPeople,but I don't understand what it means.Because In the "Per" Problem I found out How many apples go for each person.But here I'm confused as there is no Per.
    Can anyone help me?

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    Perhaps writing all as fractions, keeping an eye on the units would help.

    The first
    [tex]\dfrac{8\;apples}{4\;persons} = 2\cdot\dfrac{apple}{person} = 2\;apples\;per\;person[/tex]

    The second - literally translated
    [tex]2\;apple\cdot 5\;person = 10\;personapples[/tex]

    Pretty clearly, this makes no sense. What's a person-apple?

    If we think about the intent, we may see that what is meant is:

    [tex]2\;apples\;per\;person\cdot 5\;person = 2\cdot\dfrac{apple}{person}\cdot 5\;person = 10\;apples[/tex]

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    Last edited by tkhunny; 02-28-2018 at 07:42 AM.
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    Elite Member stapel's Avatar
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    Quote Originally Posted by Shunya View Post
    I know that 8 apples per 4 persons is = 2 apples per person.
    But What is the meaning of 2 apples * 5 people ?
    I got 10 applesPeople,but I don't understand what it means.
    If they really asked you to explain "(2 apples) * (5 people)", then... well, they're a bit strange....

    There actually is a context in which this sort of computation can make sense. If you think about workers completing a task (like fixing your car, say), the "labor" charge is not computed in terms solely of how many hours the task required, but also in terms of how many workers toiled to complete the task. While "workers" is genderless, the unit for the "labor" charge is usually called "man-hours", where the hyphen here is just a hyphen; it does not represent subtraction.

    So if it took one guy three hours to fix your car, you'd been charged for three man-hours of labor. But if it took two guys one hour, plus another hour that they worked with the manager (who is discovering that she really needs to find better help), then the "labor" charge would be (one hour)*(two people) plus (one hour)*(three people), or 2 man-hours + 3 man-hours, for a total of 5 man-hours.

    But I have no idea what your book might possibly mean by "man-apples".

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    Quote Originally Posted by stapel View Post
    If they really asked you to explain "(2 apples) * (5 people)", then... well, they're a bit strange....

    There actually is a context in which this sort of computation can make sense. If you think about workers completing a task (like fixing your car, say), the "labor" charge is not computed in terms solely of how many hours the task required, but also in terms of how many workers toiled to complete the task. While "workers" is genderless, the unit for the "labor" charge is usually called "man-hours", where the hyphen here is just a hyphen; it does not represent subtraction.

    So if it took one guy three hours to fix your car, you'd been charged for three man-hours of labor. But if it took two guys one hour, plus another hour that they worked with the manager (who is discovering that she really needs to find better help), then the "labor" charge would be (one hour)*(two people) plus (one hour)*(three people), or 2 man-hours + 3 man-hours, for a total of 5 man-hours.

    But I have no idea what your book might possibly mean by "man-apples".



    Thanks for the Reply,Stapel!
    I think I understand it now.
    The man is modifying hour,denoting that it's the man's hour being used. Am I correct?
    But(say) 7 apples*3 =21 apples.
    Because of 7apples+7apples+7apples (3 times)
    How is it possible to explain man hour from that method?
    But For 3 man* 2 hours, How can I understand man-hours in terms of addition?

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    Man-hours in terms of addition

    Thanks for replying Stapel!!
    I understood the Man-hour problem,so the meaning of Man-Apples would be similar to the Man-hour problem. Am I right?
    For 3 Men * 2 hours = 6 Man-hours.
    How can I understand it in terms of addition?
    Is it 3 man-hour + 3 man-hour ?Is this correct.
    Because for 7 apples * 3 =21 apples (7 apples +7 apples + 7 apples)(I have only one noun "Apples")(But In case of man hours there are two nouns(Man and hours)).

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    Quote Originally Posted by Shunya View Post
    Thanks for replying Stapel!!
    I understood the Man-hour problem,so the meaning of Man-Apples would be similar to the Man-hour problem. Am I right?
    Here's my attempt. In the kingdom of Applandia looking at an apple gives a person magical energy measured in man-apples. 1 man-apple is good for $3.14 at their Apple stores. We get a total of 21 man-apples from either 7 people looking at 3 apples or 3 people looking at 7 apples.
    How do you like them apples?

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    Quote Originally Posted by lev888 View Post
    Here's my attempt. In the kingdom of Applandia looking at an apple gives a person magical energy measured in man-apples. 1 man-apple is good for $3.14 at their Apple stores. We get a total of 21 man-apples from either 7 people looking at 3 apples or 3 people looking at 7 apples.
    How do you like them apples?
    Those are just peachy!!
    “... mathematics is only the art of saying the same thing in different words” - B. Russell

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    Elite Member stapel's Avatar
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    Quote Originally Posted by Shunya View Post
    Thanks for replying Stapel!!
    I understood the Man-hour problem,so the meaning of Man-Apples would be similar to the Man-hour problem. Am I right?

    In formatting, yes. In meaning, I have no frigging clue.

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