[Maths-Education] Ratio and Proportion

[Dave Wilson]

Please help me to understaqnd these 2 words! I don't think that I 
have ever been particularly bothered about them before, despite years 
of teaching using texts with chapter titlse like Ratio and Proportion.

I was looking at the NNS Key Stage 3 and read;

Year 7 pupils should use read and write, spelling correctly ratio, proportion.

It then goes on to say;

Proportion compares part to whole
offering examples - 24 fish in a pond, 6 are gold, 18 black .... the 
proportion of goldfish is 6 out of 24

and a page later;

Ratio compares part to part


These distinctions are not part of my understanding of the words. Am 
I missing something? Is this something I should know? Am I being 
mislead in terms of current usage by some hazy recollection of old 
Euclid/Heath usages?

regards,
-- 
Dave
Dave Wilson  (D.Wilson@mmu.ac.uk     A letter always reaches its 
destination                 Dave@zizek.demon.co.uk)              Lacan
http://s13a.math.aca.mmu.ac.uk