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## #1 2014-07-25 05:57:20

Al-Allo
Member
Registered: 2012-08-23
Posts: 324

### Proportion

All the proportions which we have deduced from a:b::c:d may be represented generally as follows :

ma+nb:pa+qb::mc+nd: pc + qd

For the product of the extreme terms is mpac+npbc+mqad +nqbd; which, since ad = bc, becomes mpac+npbc+mqad +nqbd; also the product of the mean terms is mpac+mqbc+npad+nqbd; or, since ad = bc, it is mpac+npbc+mqad +nqbd: so that the two products are equal.

Here are some of the proportions deduced from a:b::c:d   :

(a-b):a::(c-d):c
(a+b):a::(c+d):c

and some others (I'm not putting all of them.)

I don't understand the part : "All the proportions which we have deduced from a:b::c:d may be represented generally as follows :

ma+nb:pa+qb::mc+nd: pc + qd"

What does it mean ??? I'm not following for a certain reason....

Thank you!

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## #2 2014-07-25 08:45:31

Al-Allo
Member
Registered: 2012-08-23
Posts: 324

Bump!

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