It would make more sense to consider this symbolically
If you have min = $x$, max = $y$, then you have a range $y-x$
to calculate where a number $z$ lies on this range calculate
$200 \times (z-x)/(y-x) - 100$
For your example:
$ 200 \times(3.54-3.32 )/(4.32-3.32)-100 = -56$
Neither of your two examples matches your description: instead of $(85,5,10)$, I would have expected $(81,9,10)$, because that preserves the ratio $a:b$, i.e., $90:10=81:9$. Maybe there was a miscalculation?
If that's the case, then here's the idea: suppose you have some percentages $(a,b,c,d)$ and you're changing $d$ to $d+\Delta$. Then we need to remove a total of $\Delta$ from the other three while preserving the ratio $a:b:c$.
Looking at $a$ as a fraction of $a+b+c$, we have $\frac a{a+b+c}$. This is the fraction of $\Delta$ by which $a$ must decrease, so the new value of $a$ will be
$$a - \left(\frac a{a+b+c}\right)\Delta,$$
which after factoring out the $a$ we can rewrite as
$$a\left(1 - \frac \Delta{a+b+c}\right).$$
To put it more simply, let $T$ be the total of the first three values: $T=a+b+c$. Then the new value of $a$ will be $a\left(\frac{T-\Delta}T\right).$
The changes to $b$ and $c$ are similar; therefore, the new values of $(a,b,c,d)$ will be
$$\left(a\left(\frac{T-\Delta}T\right), b\left(\frac{T-\Delta}T\right), c\left(\frac{T-\Delta}T\right), d + \Delta\right).$$
Finally, note that the case $a=b=c=0$ will have to be given special treatment.
Best Answer
Percentages add up to 100, so 100 - p = f