Maths Bods, You Are Needed

[Gibsie]

Aloha, I have a little bit of a calculation to complete, as follows:

58.4 = ln(1-1.95c)/ln(1-0.05c)

So errr is there a simple way of working out what c is (if it is a value at all)? It's been too long since I done proper maths... I know I can raise everything by e^x to give

e^58.4 = (1-1.95c)/(1-0.05c)

but I still dunno where to go from there, cos I'm rubbish! Any helps?

[loinburger]

20

[loinburger]

say that e^58.4 is Z. So you've got
Z = (1-1.95c)/(1-0.05c)
Z(1-0.05c)=1-1.95c
Z - 0.05cZ = 1 - 1.95c
Z - 1 = 0.05cZ - 1.95c
(Z - 1) / (0.05Z - 1.95) = c
(e^58.4 - 1) / (0.05 * (e^58.4) - 1.95) = c

[Gibsie]

And there I was thinking 20 was just a joke response! Thanks

[loinburger]

Yeah, I figured it needed a bit more explanation when it came out to such a nice answer

[Lul Thyme]

Aloha, I have a little bit of a calculation to complete, as follows:

58.4 = ln(1-1.95c)/ln(1-0.05c)

So errr is there a simple way of working out what c is (if it is a value at all)? It's been too long since I done proper maths... I know I can raise everything by e^x to give

e^58.4 = (1-1.95c)/(1-0.05c)

but I still dunno where to go from there, cos I'm rubbish! Any helps?

Even your first step is wrong.
e^((ln a)/(ln b)) is not a/b, it's a^(1/ ln b), so loinburger was working on a different problem than your original one.

Also, if c=20, then neither equation is defined, since (1-0.05c) is 0, so you either have denominator 0 or log 0.

[Docfeelgood]

I once saw a dog try to hump a cat.

[Egbert]

Was the attempt successful?

What would you call the offspring?

[Docfeelgood]

What would you call the offspring?

Oh... so..... tempting......I....must.......resist..........

[Lul Thyme]

Couldn't find an analytical solution.
Online mathematica finds c approx 0.301801.

http://www.wolframalpha.com/input/?i=58.4+%3D+ln%281-1.95x%29%2Fln%281-0.05x%29

Whenever you solve something like this, it's always good to sanity check and plug back whatever you find back in the original problem.

[Docfeelgood]

Oh man, I sure do regret putting those crayons down in the 3rd grade and dropping out of school.

[Docfeelgood]

I followed that link........wow! you guys are smart.

[Gibsie]

Yeah I figured there was a problem somewhere when I put in a different value in place of the 58.4 part and the result was 20 again! Plus the concept of the question should give an answer between 0 and 1 as well, so, thanks again