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Monday, November 22, 2010

hw #4-2 Graphs, Graphs, and more Graphs

The best way to learn graphing is to make graphs, and make mistakes along the way.  To minimize mistakes, try keeping scrap paper handy to quickly sketch and checking your scaling.

hw #4-2
pg 243-245 #1-13 ALL, 15-18 ALL

20 comments:

  1. I have a question on test corrections.. For the last question. :( I don`t understand the extra '27' people I think.. And how they affect the amount of people that are in I think butter or creamcheese?
    I'm sorry I don't have the test with me.:(

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  2. Yup, you really do need the test with you when making test corrections. Don't forget, when you hand-in the test corrections, I need the test as well.

    This was the problem:

    Of 325 7th graders (Set U – Universal), 163 will eat bagels with butter (Set B), 148 will eat bagels with cream cheese (Set C), 216 will eat bagels plain (Set P). Some will not eat bagels at all (Set D). Furthermore:

    23 will eat bagels either with butter or cream cheese, but not plain
    32 will eat bagels with butter, cream cheese, or plain
    67 will eat bagels either with butter or plain, but not with cream cheese
    27 will eat bagels only with cream cheese

    You should be able to draw a Venn Diagram with this information AND THEN figure out how to calculate the missing information to complete the diagram.

    The questions referred to the missing information:

    How many students will eat only bagels with butter?
    How many students will eat only plain bagels?
    How many students will not eat bagels at all?


    Let me know if this helped.

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  3. What I meant was, how did the 27 people only with creamcheese affect the creamcheese?
    And how was there a cross between cream cheese & plain?

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  4. Also, my answer for 12a. was 35>t>=80
    And I got -1/2

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  5. I was also confused on #7.. My answer was x<6 1/3 or x>= 4

    But I got that wrong, and apparently I graphed it wrong, I graphed it as an "AND" inequality, I didn't know any other way. :(

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  6. I'm not sure I understand your questions about the bagels. Maybe you are confusing the way people like bagels with how the bagels are prepared? In other words, I can like bagels with butter and I can like bagels plain, but I can't eat a bagel that is both plain and buttered at the same time.

    27 of the students like bagels ONLY with cream cheese... they do NOT like to eat them plain or with butter.

    It is possible for someone to like a bagel either plain or with cream cheese, but not with butter.

    For #12a: "OR inequalities" are not permitted to be written in shorthand form. The shorthand form implies that t<35 and t>=80 at the same time, which as you do understand, is not possible. Shorthand is reserved for AND inequalities.

    For #7: Yup, you're right... you got it wrong. You got the x>=4 part right, but the problem was clearly stated as an "or" inequality.

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  7. Thank you, but I still don't understand the last one. After they already stated the amount of people that eat creamcheese, they are stating another amount that will eat ONLY creamcheese? Is that added on to the amount of people????
    ?_?

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  8. Yup. Of the 148 that will eat bagels with cream cheese, some also like butter, some also like plain, and some like both butter and plain. However some will only eat bagels with cream cheese. You need to draw a 3-circle Venn diagram similar to the one found on pg 216 to see all of the possibilities. The big circles would be Cream Cheese, Butter, and Plain. In this bagel problem, there is a fourth circle (disjoint i.e. non-intersecting) that represents students that don't eat bagels at all.

    I appreciate that you are trying to understand. Let me know if this helped.

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  9. I understand the whole concept of the Venn Diagram, I just don't understand what to do with the "27 that will eat bagels only with creamcheese" ?

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  10. I also have a few questions for homework, sorry it`s so late.
    #3 confuses me, what other dependent variables could there be other than amount of toothpaste?
    I don`t really understand #4. I don`t understand the definition of function for that question...
    AAANNDDD.. I could not find functions for 10-13.
    Lastly, hopefully, I don't understand #15.

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  11. Dear Pumpernickel,

    If one of the big circles is the Cream Cheese circle, the 27 would go in the only part that DOES NOT INTERSECT with either of the other two circles.

    I appreciate your persistence... why not show up in room 220 before homeroom and we'll go over it on the board? I'll write you a pass to homeroom!

    Mr. C.

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  12. We'll definitely go over the homework in class.

    For #3, why is the toothpaste leaving the tube? It's dependent on what?

    For #4, you need to review the definition of a function on page 241. See if you can get it then.

    We'll discuss the rest in class. Get some sleep. I expect you to try, not pull your hair out. You'll see the patterns when we go over things tomorrow.

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  13. Okay, thank you, And I'll stop by in Homeroom!

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  14. P.S. I still can't figure out how to graph #7 on the test for my test corrections..

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  15. that's cuz you aren't solving the LEFT inequality correctly...

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  16. I'm working on it...
    And should I come during homeroom?

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  17. OHHHHHHHHHHH Now I see.. I missed the negative sign on -6 1/3..

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  18. Yeah... stuff happens!

    I will arrive at FMS at or around 7:30am... you are welcome any time after that.

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  19. heyy Mr. C can u make a new bolg for 4-3

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