Introduction
Courtney cannot make either the biggest or the smallest
numbers. She interprets the decimal part as the denominator
of a fraction. She then uses her fraction knowledge that "the
more pieces something is divided into, the smaller each one
is". Comments: Text in italics
Interviewer: Text in red
Courtney: Text in other colour |
Interviewer:
I have a number that starts 3 point something
something... |
Interviewer:
and you get to choose the rest of the
number... |
Interviewer:
Here are the cards to choose from marked
0,1,2,3,4,5,6,7,8 and 9. I'm going to ask you to make the biggest
number that you can by choosing any two of these cards. |
Courtney chooses only one card to make 3.1
Courtney:
Well, it might be 3 point 1 but I'm
not sure.
Interviewer:
Tell me what you're thinking.
Courtney:
Well, if it was three point two or three
point seven eight then there'd be more pieces so they'd have
to be smaller. So I guess just three point one.
Interviewer:
OK, what about if you have to choose two
of the cards to make your number?...... |
Courtney makes 3.01 |

Interviewer:
Could we just look at those two numbers
that you made? Did you make it bigger or smaller when you changed
it?
Courtney:
Ummm, I think they're the same...cause
the zero doesn't matter.... |
Interviewer:
OK, now we'll put those cards back ....and
could you make another number, this time as small as you can? |
Courtney:
Three point nine eight would be
the smallest
Interviewer:
Why's that?
Courtney:
Because if it's cut into lots of
pieces, they must be small. |