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 Thanks for the link. Bookmarked
M.D.V. 
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
Rating helpful answers is nice, but saying thanks can be even nicer.
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It's trivial https://codeproject.global.ssl.fastly.net/script/Forums/Images/smiley_wink.gif, even after almost 60 years away from Grammar School in England. The steps are, using C formulae:
a / (a + b) = c / d
Multiply both sides by (a + b)
a = (a + b) * c / d
Collect the terms in a
a - a * c / d = b * c / d
Collect the coefficients of a
a * (1 - c / d) = b * c / d
Divide both sides by (1 - c / d)
a = b * c / d / (1 - c / d)
Simplify
a = b * c / (d - c)
Hope that's right, solved before you would have found the program
In those good old days you got the algebra beaten into you
Show-off Jerry
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... and c needs to be not equal to d ...
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I am so grateful for a post from someone who doesn't feel being innumerate is a way to be part of some team.
Like the slope-of-a-line question. dy/dx - WTF's the difficulty with high school math?
Something akin to pride as a consequence of membership in a pool of those who "can't" seems to be spreading from the TV and Radio to CP. Maybe the problem with poor code isn't only from the mass-production hordes now being unleashed?
Alas.
| Ravings en masse^ |
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| "The difference between genius and stupidity is that genius has its limits." - Albert Einstein | | "If you are searching for perfection in others, then you seek disappointment. If you are seek perfection in yourself, then you will find failure." - Balboos HaGadol Mar 2010 |
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Probably took me the same amount of time by a slightly different route:
a/(a+b)=c/d
Multiply both sides by (a+b) and by d
ad = c(a+b)
Expand
ad = ac + bc
Subtract ac from both sides
ad - ac = bc
Collect the coefficients of a
a(d-c) = bc
Divide both sides by (d-c)
a = bc/(d-c)
Oh, if only all the equations were linear.
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Probably took me the same amount of time by a slightly different route:
You're right, I thought of this after having written the route.
Jerry
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I got a slightly different (if not simpler) answer.
a/(a+b) = c/d
a = c/d*(a+b)
a*d/c = a+b
a*d/c -a = b
a*(d/c -1) = b
a=b/(d/c-1)
Which if you multiply the numerator & denominator by c you'll get the answer the machine reports.
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a/(a+b) = c/d
a = c(a+b)/d
a = ca/d + cb/d
a - ca/d = cb/d
ad - ac = cb
a(d-c) = cb
a = cb/(d-c) A slightly different version from Jerry's. I had 32 credit-hours of math in college - calculus, differential equations, and matrix algebra. All of it's gone, with the space in my head now used for old movie lines. The algebra's stayed around, as it seems to come in handy now and then.
Software Zen: delete this;
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As a math minor I suddenly understand the disdain for cliffs notes...
LOL
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kmoorevs wrote: a/(a+b) = c/d where I was solving for the variable a.
It's a lot easier to see the solution when one writes it like:
a c
------ = ---
a + b d
I'm a firm believer that visualizing (or expressing) the problem correctly is 90% of the solution.
Given the above, cross multiply to get:
ad = c (a+b)
then:
ad = ca + cb
ad - ca = cb
a(d-c) = cb
cb
a = ---------
d-c
Latest Article - A Concise Overview of Threads
Learning to code with python is like learning to swim with those little arm floaties. It gives you undeserved confidence and will eventually drown you. - DangerBunny
Artificial intelligence is the only remedy for natural stupidity. - CDP1802
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oh wow, thanks. helped prove that the following does simplify
(A / (B * C) ) * B
simplifies to
A / C
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... drinking 8 glasses of water a day seems impossible, but 8 beers and 7 shots goes down like a fat kid on a seesaw?
Sent from my Amstrad PC 1640
Bad command or file name. Bad, bad command! Sit! Stay! Staaaay...
AntiTwitter: @DalekDave is now a follower!
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It also makes drinking 8 glasses of water the next day more desirable 
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I reckon it's the environmental factors that makes beer drinking easier,
forcing down that 8th glass of water coz 'you're supposed to' is just a chore,
drinking the 8th beer because the last one went down well and you feel like continuing (esp entertaining/being entertained) is pretty much automagic.
same as eating a whole pizza
- sitting down at a table barely half way it's tough going, probably doggy-bag required.
- [lubricated with beer] during a big/live game - particularly if it's a close game... full time, still got the munchies, and you're wondering who stole the other half of your pizza.
This internet thing is amazing! Letting people use it: worst idea ever!
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OriginalGriff wrote: but 8 beers
It's all a matter of which you do first. The 8 beers or the 8 glasses of water...
A Fine is a Tax for doing something wrong
A Tax is a Fine for doing something good.
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I suggest trying it out first, with the beers, just to see if you can do it.
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