Hi. If I am not mistaken, I think the values above 20 are double-added. I
get slightly different answers.
I'll take a crack at it, but I may be wrong...
For this example, enter a weight in pounds in A1. In another cell with a
range name "kg", enter...

=CONVERT(A1,"lbm","kg")

The Op wasn't clear on what value he was using for over 20, but I'll call
that value "Q".
If we set "Q" equal to about 20, we get values that are close to his
example...
Here is your excellent equation slightly modified:

=MIN((25*Kg)/6,(25*(Kg+10))/12,(Q*(Kg-20)+1500)/24)

I like to use Range Names when the equation gets a little out of hand...
Hope I got this right...
--
HTH. :)

Dana DeLouis
Windows XP, Office 2003


"MC" wrote in message
. com...
Robin,

I checked my answers against the ones we gave for 15, 40, and 70 lbs and
got basically the same answers with small rounding errors due to Excel's
12-digit precision versus hand calculations. Perhaps my earlier response
was confusing. You only have to enter numbers one time in Excel and from
there forward if you want to only change the weight, the spreadsheet
calculations will flow all the way through. There is no need to re-enter
numbers previously entered if they do not change. This is the beauty of
Excel. However, if you prefer a single formula that simply takes the
child's weight and calculates the fluid then it would be the following:

Enter the weight in pounds in cell B3
Copy the following formula to any cell:
=(IF(B3*0.453593=10,10*100/24,B3*0.453593*100/24)+IF(B3*0.453593=20,10*50/24,IF(B3*0.453593=10,(B3*0.453593-10)*50/24,0))+IF(B3*0.453593=20,(B3*0.453593-20)*20/24,0))*24

As you can see it is pretty long, but get's the job done. I initially
structured my response to allow the flexibility of changing the fluid
rates because you sounded like the amount of fluid above 20 kg could range
between 10 to 25 ml/kg/24 hr. The disadvantage of the formula above is 20
ml/kg/24 hr is hardcoded into the formula. Therefore if you wanted to
change this value you would have to edit the formula in Excel which is far
from an elegant approach subject to mistakes and I would not recommend it.

Hope this helps!

MC

"Robin" wrote in message
...
Your formula is close - I have figured it out with pencil and paper and
it
is very close but I am just trying to figure out a volume not a rate - so
the
only value I have to input is the 15 pounds. From that all of the
numbers
should fall out. So on paper it looks like this.

This is the problem:

1. Convert child's wt in lbs to kg
2. Calculate 100 ml of fluid/kg/24 hr for the 1st 10 kg of wt
3. Calculate 50 ml of fluid/kg/24 hr for the 2nd 10 kg of wt
4. Calculate 10 to 25 ml of fluid/kg/24 hr for each kg over 20 of wt
5. Add the products of steps 2,3, and 4 to determine the ml of fluid
needed/24 hrs

This is the solution on paper:

Maintenance Fluids
15lb - 28.4ml/hr for a total of 681.6ml/24 hours
40lb - 58.6ml/hr for a total of 1,406.4ml/24 hours
70lb - 72.3ml/hr for a total of 1,735.2ml/24 hours

So again the only input is the weight in pounds.

You are so kind to help me and I hope this will not offend you. Thanks
for
taking another look at it. I am using your suggestions and trying to
build it
from there but I think it is hard to understand without a medical
background.
If the child ends up not weighing over 10kg then the amount of fluid is
just
100ml/kg, but if the child weighs more than 20kg then I have to figure
100ml
for the 10kg + 50ml for the next 10kg + 20ml for each additional kg.

I think we are so on the right track - just a little refining. I used to
write stuff in Excel all the time but that was a long time ago and I just
don't remember it anymore. Again THANKS SO MUCH for looking at this.

"MC" wrote:

Oops! Make sure to change all the B3 references in the IF...THEN
statements
to reference B4.

MC

"M C Del Papa" wrote in message
et...
Robin,

You definitely don't need a macro to do this. A simple formula using
some
IF...THEN statements will do fine. Below is one approach (note I
skipped
some rows and columns so you can add headings, etc.):

Enter wt in cell B3
Convert to kg in B4: =B3*0.453593

Enter desired fluid rate for 1st 10 kg in B7
Calculate fluid rate in C7: =IF(B3=10,10*B7,B3*B7)
Enter desired fluid rate for 2nd 10 kg in B8
Calculate fluid rate in C8: =IF(B3=20,10*B8,IF(B3=10,(B3-10)*B8,0))
Enter desired fluid rate for 20 kg in B9
Calculate fluid rate in C9: =IF(B3=20,(B3-20)*B9,0)

Sum in cell C10 to get the total fluid rate: =SUM(C7:C9)

MC

"Robin" wrote in message
...
Hi I don't know how to do this but I know it can be done. I want to
write a
simple macro (or maybe just a formula) - it doesn't have to look that
pretty
as I am the only one using it. It is the following:

STEPS TO CALCULATE USUAL MAINTENANCE FLUIDS:
1. Convert child's wt in lbs to kg
2. Calculate 100 ml of fluid/kg/24 hr for the 1st 10 kg of wt
3. Calculate 50 ml of fluid/kg/24 hr for the 2nd 10 kg of wt
4. Calculate 10 to 25 ml of fluid/kg/24 hr for each kg over 20 of wt
5. Add the products of steps 2,3, and 4 to determine the ml of fluid
needed/24 hrs


So I want to be able to plug in a weight in pounds, and this "macro"
give
me
the individual answers for each step, then the total at the end. And
yes
I
can do it on paper all day long I just want to be able to do it
quicker
and
check myself.

Thanks
Robin