[Maths-Education] Not just Ratio and Proportion

[Dick Tahta]

Has Dave Hewitt played a joker?

>Let me see now... circumference of a circle is pi multiplied by
>diameter. If my diameter is, for example, 11.37cm, in what way
>does the image of repeated addition help me with this
>multiplication?

What is this pi that he is mutiplying by?   Not I suppose a rational
approximation for in that case the multiplication would be equivalent to
that of integers and so equivalent to a repeated addition.  But what does a
multiplication by an irrational look like?  Is this issue related to the
ancient problem of determining the "ratio" of circumference to diameter?
I can certainly see repeated subtractions in a calculation of that.

Dick Tahta