Need help on a math calculation anyone good at dimensional anlysis?

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I am stuck on a math problem...new to learning dimensional analysis. Could someone help please. Thanks so very much!

Here is the problem Order for ensure 240 mL over 90 minutes q 6h. Following each feeding, replace 40 mL water for every 100 mL urine output. The patient's output of urine for the last 6 hrs was 300 mL.

Specializes in ED.

The Nursing Math help thread is that way -------->

There is a sticky at the top of this forum. It is your BFF for all things math.

This is a pretty straightforward question. I think you either not reading / understanding what it is asking or you are over-thinking it.

Specializes in student; help!.

You just need to calculate the H20, no? It doesn't look like the Ensure matters a whit. It's simple math you should be able to do in your head if you know which numbers to use. Really!

You don't need any DA for this problem.

When I see people asking math problems like this I get worried. You are not looking at the problem. Go to your college and find out when the math tutor center is open. *Most* nursing math problems you should be able to just figure out based on relationships and things. I know math is harder for some people than others, but it is going to get A LOT WORSE than this problem, and if you can't get your grounds with this kind of problem, you'll be in trouble. I'm not trying to be harsh, I promise! Please get yourself some grounding in math so you don't have to struggle through calculating drip factors by gravity and figuring out what percent concentration of a medication is in a solution.

Specializes in Management, Emergency, Psych, Med Surg.

This is an easy problem but I am not sure that the question is. Are you asking how much fluid to give in addition to the ensure or are you calculating the total volume that the patient will receive in 24 hours? I don't understand exactly what your asking.

Specializes in Trauma, Teaching.

The first thing you need to do, is figure out what is being asked. You have not given the entire question, because we don't know what you are being asked to figure out. Look at your question again (not what is posted, what is in your book). Are you being asked how much water you follow the feeding with? Are you being asked for total volume going in?

In general, DA is very straight forward.

Put the unknown, what you are being asked for, on the left. "x" unknown =

put the data that you will need on the right: (available) x (dose) x (conversion factors) set up the equation so the "units" cancel out (mgs, kg,s, mLs, mcgs), and all that is left are the "units" in your wanted answer. Then plug in the numnbers to go with each of those units.

If you are being asked how much water to give:

x mLs H2O = 40 mLs H2O/ 100 mLs urine x 300 mLs urine. The "urines" cancel out, leaving only "H2O"

I am stuck on a math problem...new to learning dimensional analysis. Could someone help please. Thanks so very much!

Here is the problem Order for ensure 240 mL over 90 minutes q 6h. Following each feeding, replace 40 mL water for every 100 mL urine output. The patient's output of urine for the last 6 hrs was 300 mL.

I agree with other posters....there's no question mark in what you typed. What is the question?

Specializes in Wound Care, LTC, Sub-Acute, Vents.
i am stuck on a math problem...new to learning dimensional analysis. could someone help please. thanks so very much!

here is the problem order for ensure 240 ml over 90 minutes q 6h. following each feeding, replace 40 ml water for every 100 ml urine output. the patient's output of urine for the last 6 hrs was 300 ml.

what is the question?

is it how many total of water was supposed to be given in the last 6 hours? if so,

then divide the 300 ml with 100 ml (300/100), so you would get 3. then you must multiply that 3 with 40 ml and you get 120 ml. so 120 ml of water was supposed to be given in the last 6 hours.

however, if the question asks for the total input in the last 6 hours, then you add 120 ml of water and 240 ml of ensure, so the total input in the last 6 hours is 120 + 240 = 360 ml

let me know if you need further explanations.

angel, rn

Previous poster gave you one way of solving this problem. It's probbaly easier that way. You don't need to use dimentional analysis for this, but you could if you want to. Here's how.

We need to find the amount of water you give to your patient after his 240 ml of ensure.

"y" is what we need to find, it's the unknown.

Pt needs 40 ml of water for 100 ml of urine. Pt needs y ml of water for 300 ml urine. You mirror these two parts in the formula:

40/100 = y/300

(40ml of water is the same to 100 ml of urine as y ml of water to 300 ml of urine. it's actullay easier to see if you write it down with numbers on top and bottom instead of slashes, but I don't have that function on my keyboard)

You place the same values in the same positions and mirror them. For instance, you would write 40/300 =x/100 if the quesiton would have been "give patient 40 ml of water for every 300 ml of urine , how much water you need to give for every 100 ml of urine?)

So

40/100=y/300

(it's simply a=y/b

y=a X b)

y = 4/100 X 300

y=4/100 X 300/1

y= 12000/100

y=120

You need to give 120 ml of water to your patient with his 240 ml of ensure.

If you need to calculate total volume you give him, you just add 120 to 240 =360 ml

I am stuck on a math problem...new to learning dimensional analysis. Could someone help please. Thanks so very much!

Here is the problem Order for ensure 240 mL over 90 minutes q 6h. Following each feeding, replace 40 mL water for every 100 mL urine output. The patient's output of urine for the last 6 hrs was 300 mL.

What's the question? For every 100 mL of pee squirt in 40 mL of water.

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