Fraction (or Fractured?) Understanding

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Fraction (or Fractured?) Understanding Debi DePaul

PROFESSIONAL LEARNING www.origoeducation.com

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Represen,ng  Frac,ons Teachers  and  students  need  to  consider  the   following: – The  type  of  quan,ty  (con,nuous  or  discrete?)  that   the  model  is intended  to  represent.   – How  the  whole  is  defined. – What  equal-­‐sized  means  in  the  model. – What  the  frac,on  indicates.

Represen,ng  Frac,ons  

Represen,ng  Frac,ons

The  number  –  a  discrete  (countable)  quan,ty  

The  area  –  a  con,nuous  (measureable)  quan,ty  

The  whole  is  determined  by  a  defined  count     of  a  collec,on  or  set.  

The  whole  is  determined  by  the  defined  area  or   region.  

The  same  number  of  items  represents  equal-­‐sized  parts.  

The  same  area  represents  equal-­‐sized  parts.  

The  frac,on  indicates  the  count  of  objects  in  the  subset   compared  to  the  defined  set  of  objects.  

The  frac,on  indicates  the  area  of  the  part   compared  to  the  area  of  the  whole.  

Set  Model

Area  Model

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Represen,ng  Frac,ons

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1 2

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1 3

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Length  Model

Represen,ng   Frac,ons 0 1 Number  Line  Model  

The  length  –  a  con,nuous  (measureable)  quan,ty  

The  distance  –  a  con,nuous  (measureable)  quan,ty  

The  whole  is  determined  by  a  defined  length.  

The  whole  is  determined  by  a  unit  of  distance     from  0  to  1.  

The  same  length  represents  equal-­‐sized  parts.  

The  same  distance  represents  equal-­‐sized  parts.  

The  frac,on  indicates  the  length  of  the  part   compared  to  the  length  of  the  whole.  

The  frac,on  indicates  the  loca,on  of  a  point  in  rela,on  to   the  distance  from  0  with  regard  to  the  defined  unit.  

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1 3

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A  special  type  of  length  model.  

© ORIGO Education

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con'nuous  

Length   model  

con'nuous  

con'nuous  

Area   model  

Number  line   model  

discrete  

Type  of   Quan/ty  

Set   model  

Type  of   Model  

unit  of  distance   from  0  to  1  

determined  by  a   defined  length  

same  distance  

same  length  

same  area  

same  number   of  items  

determined  by  a   defined  count  of  a   collec'on  or  set  

determined  by  a   defined  area  or  region  

Meaning  of     Equal-­‐Sized  Parts  

Whole  

the  loca'on  of  a  point  in   rela'on  to  the  distance  from  0   with  regard  to  the  defined  unit  

the  length  of  the  indicated  part   compared  to  the  length   of  the  indicated  whole  

the  area  of  the  indicated  part   compared  to  the  area  of  the   indicated  whole  

the  count  of  objects  in  the   subset  compared  to  the   defined  set  of  objects  

What  the  Frac/on  Indicates  

Represen'ng  Frac'ons