# Very big thanks for this forum and a request for help

#### timb100

##### New member
Hello good people

I'm very great-full if you get this far and actually read my question.

Just so you know this is not a homework question. I have my own sole trader business, nothing to do with maths but this question will be used as part of future R/D work for myself. I am rubbish at maths but I try very hard to muddle through. I really appreciate the help if you offer any.

The equation I am trying to solve is the following.

I have an air/water mix ratio (AW)
I know how long it takes to fill a vessel (T) so I'm left with just water with a set AW ratio eg 99% air 1% water takes a time = 4 (T = 4)

What I need to work out is how to reverse the calculation

So I know that and AR of 99 results in a T or 4
What would be the formula to work out what AR is based on a change to T

EG AR of 99 Expected time T = 4
Found a T of 3.8 What is actual AR?

Again really appreciate if you can help. Happy to buy a few coffees for anyone who can help

Tim

#### Harry_the_cat

##### Elite Member
By AR, do you mean AW?

#### JeffM

##### Elite Member
If I understand the question (and I am not sure I do), it is not solvable. You cannot deduce a general relationship from a single observation. You would need to experiment and generate multiple observations to have any confidence in a general relationship. Make sense?

#### timb100

##### New member
If I understand the question (and I am not sure I do), it is not solvable. You cannot deduce a general relationship from a single observation. You would need to experiment and generate multiple observations to have any confidence in a general relationship. Make sense?

I really do not know if its not possible. From the maths I have done I can get near but my maths lets me down on the last bit. I see no variables that will effect what I'm looking to achieve.

Here is some of my maths

Flow of air water mix per hour is 1.30677kg/h
Time to collect 100ml is 275.488418 seconds based on this algo ((0.1kg*60)/1.30677kg)*60
If you add 2% to the 1.30677kg/h you get a volume of 1.3198377kg then do the timing calc you get time to fill of 270.0866843 seconds

However I think my maths is wrong as I did not do the maths of the adding 2%. I feel I added too much as I added 2% to original figure not changed the % in the original volume.

As you can see I can calculate the time ok. I need as I said know the time it should take then from the time it did take work back to the %

Cheers and thanks

Tim

#### timb100

##### New member
Thanks peoples

Just to say I worked with a friend on this and worked out the answer.

Really appreciate your help so far.

Cheers
Tim