Chap 2: Real Numbers - Spot the Common Mistakes (I)

Revision Exercise 2 (p52 of Textbook) No. 7(a)

22 comments:

  1. (-16) x (-3) - (-8) x 5
    = 48-(-40)
    =88

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  2. (-16)X(-3)-(-8)X5
    =48--40
    =88

    Ziying

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  3. (-16) x (-3) - (-8) x 5
    =48 - (-8) x 5
    =48 + 8 x 5
    =48 + 40
    =88

    ReplyDelete
  4. (-16) x (-3) - (-8) x 5=48 + (8 x 5)
    =48 + 40
    =88

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  5. (-16)x(-3)-(-8)x5=48-(-40)
    =48+40
    =88

    ReplyDelete
  6. The sum sentence should be 48--40 but the person took it as 48-40

    Note that -8X5 is -40 so there is an extra negative sign

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  7. (-16)x(-3)-(-8)x5
    =48+40
    =88
    Ans: 88

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  8. (-16)x(-3) - (-8) x 5
    =48 - (-40)
    =88

    ReplyDelete
  9. It should have been:
    (-16) X (-3) - (-8) X 5
    = 48 - (-8) X 5
    = 48 + 40
    = 88

    The mistake was 48 - 40 when it should actually be 48 + 40.

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  10. (-16) x (-3) - (-8) x 5
    = 48 -(-40)
    = 88

    chengngee

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  11. (-16)x(-3)=48
    (-8)x5=(-40)
    48-(-40)=88
    Ans:88

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  12. (-16)x(-3)-(-8)x5
    =48-(-40)
    =48+40
    =88

    ReplyDelete
  13. (-16)x(-3)-(-8)x5
    =48-(-40)
    =48+40
    =88
    He should do multiplication first before subtraction.

    ReplyDelete
  14. (-16)x(-3)-(-8)x5
    =48-(-40)
    =48+40
    =88

    ReplyDelete
  15. (-16) x (-3) - (-8) x 5
    =48-(-40)
    =48+40
    =88

    ReplyDelete
  16. (-16) x (-3) - (-8) x 5
    = 48 - (-8) x 5
    = 48 - (-40 )
    = 48 + 40
    = 88

    ReplyDelete
  17. Class S1-01

    Well done... all correct...

    On the presentation, please note...

    when we have 2 signs side by sign to each other,
    e.g. 48--40, we'll need to separate them with a bracket so that it looks like
    48 - (-48)

    If need to shown working for each group,
    e.g.
    (-16)x(-3)=48
    (-8)x5=(-40)

    Good to leave some space above and below so that the reader will note that this is working of smaller groups of number.
    Alternatively, can write them by the side (when working is to be done on paper).

    :D

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