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Topic: Re[2]: Intro to Number; counting and all that
Replies: 4   Last Post: Nov 8, 1995 6:21 PM

 Messages: [ Previous | Next ]
 Larry Bowen Posts: 7 Registered: 12/6/04
Re[2]: Intro to Number; counting and all that
Posted: Nov 7, 1995 3:27 PM

<<Judith said:
... They confuse cardinality and ordinality. ...>>

<<Tom sent this approach to counting:

P PP PPP PPPP PPPPP PPPPPP <-- Six groups
of pennies.

Does it help to show a series of groups of pennies? That is to say,
the first group has 1, the second group has 2, etc. If we count
the pennies in the sixth group we can count up to six, and it doesn't
matter what order we count them in. Etc. As I said, I am no expert at
this,
and both my kids seem to have picked up on numbers by watching
Sesame Street.>>

*****************

<<Judith responded

Tom:

This example works, Again I would emphasize that "six"
refers to the whole group. A sweeping of the hand or
a flashing of all 6 pennies. Electronically, I would
highlight one, then two, then three pennies, etc. .
This sets the idea that two refers to the highlighted
pennies not just the secon one or the ones not highlighted.

Judith>>

What does "works" mean? If it refers to making clear the distinction
between "cardinality" and "ordinality," I'm not sure I see how.
Larry

Date Subject Author
11/7/95 Larry Bowen
11/8/95 roitman@oberon.math.ukans.edu
11/8/95 Tom Johnson
11/8/95 Bill Juraschek
11/8/95 Judith E. Jacobs