math problem

[Guest guest]

Hi,

Several ways to solve this one. One way would be to use

ratio/proportion. In solving this we need to realize that 1:5000

means 1 gram of Active Drug / 5000 ml solution.

1. Find out how many mcg you actually have in the IV

setup: 1g / 5000 ml = x g / 10 ml

x = 0.002 g

setup: 1 g / 1000 mg = 0.002 g / x mg

x = 2 mg

setup: 1 mg / 1000 mcg = 2 mg / x mcg

x = 2000 mcg

2. Find out flow rate

setup: 2000 mcg / 500ml = 5 mcg / x ml

x = 1.25 ml

Not sure where we got 1.28 ml / minute. Since that is the closest

answer I would choose it.

Respectfully,

Joe Medina, CPhT

http://www.techlectures.com

--------------

I am having problems working the following problem:

An IV infusion contains 10ml of a 1:5000 solution of Isoproterenol

hydrochloride and 500ml of a 5% dextrose injection. At what flow rate

should the infusion be administered to provide 5mcg of isoproterenol

hydrocholride per minute?

a. 0.45 ml per minute

b. 1.28 ml per minute

c. 2.64 ml per minute

d. 4.12 ml per minute

I normally do not have a problem with flow rates, but this one I am

struggling with. Thanks for your help!

----------------

[Guest guest]

Dear All,

I had to add dash lines or hypens to use as 'spacers' or else the

numbers run together as seen in the post that I deleted

A ratio proportion looks like this with out spacers:

2 cats 10 cats

------------ = --------

1 household X households

With spacers one can make heads and tails out if it!

2 cats------------10 cats

------------ = -------------

1 household-----X households

Hope this helps you to look beyond the dash marks and to understand

why they are used.

Respectfully,

Jeanetta Mastron CPhT BS Chemistry

Pharm Tech Educator

Founder/Owner of this site!

copyeright 7-15-03 Jeanetta Mastron

> From: " Jeanetta Mastron CPhT BS Chemistry " <rxjm2002@y...>

> Date: Tue Jul 15, 2003 9:17 pm

> Subject: Re: Math Problem

>

> >

> But this new solution has 2000 mcg of Isoproterenol!!!!

> This is 2000mcg Isoproterenol/510 ml Combined Solution

>

> Settting up a ratio/porportion tells us how muchsolution would

> contain 5 mcg:

>

> 2000 mcg-------- 5 mcg

> ------------ = ---------

> 510 ml---------- X ml

>

>

> Cross Multiply = 510 x 5 / 2000

> answer is 1.275 ml

>

> which is 1.28 ml

>

> --------------------------------------------------------------------

2000 mcg 5 mcg

--------- = -------

510 ml X ml

[Guest guest]

Good call,

If we are to get even more specific, we also need to allow for the

D5W overfill. Realize answers on the examination will be far apart

enough that you will know if you are on target or not (example

below). Regardless, good call.

a. 0.45 ml per minute

b. 1.28 ml per minute

c. 2.64 ml per minute

d. 4.12 ml per minute

Respectfully,

Joe Medina, CPhT

----------------

I had a hard time with this one too. I couldn't do it on my own and

I still have a bit of a hard time following your method...but it

does make sense. I hope I can replicate something like this on the

test.

But...I think that in your final ratio/equation, you should have

510ml instead of 500ml. YOu have 10 ml of the active drug and 500ml

of the dextrose solution.

thank you so much for responding to the question. I was cross-eyed

trying to work this one. Standing on my head didn't work either!

Some of these just baffle me.

Thanks again

[Guest guest]

Thanks everyone for your help!

[Guest guest]

Dear Poster

You are most welcome!

Jeanetta

Founder/Owner

> Thanks everyone for your help!

[Guest guest]

Dear ,

Thank you for asking a study question.

Dear Lennon and Callysta St n,

Thank you for your input. a TEXPERT has not only responded with

acknowledgment of correct answers but with 'extra' help that will

enable you to answer more questions like the one posted by .

I would like to add:

D = 500

M = 1000

DC = 600

CM = 900

I do hope that this helps.

12 mg /3mg/tablet is = 4 tablets not 4mg

When a smaller roman numeral is placed before a larger onem you subtract:

IV = 5 - 1 = 4

IX = 10 - 1 = 9

CD = 500 - 100 = 400

XL = 50 - 10 = 40

When a smaller roman numeral is placed after a large one, you add:

VI = 5 + 1 = 6

XII = 10 + 1 + 1 = 12

DCX = 500 + 100 + 10 = 610

LX = 50 + 10 = 60

Some times there are combinations:

DCXL = 500 - 100 and 50 - 10 = 400 and 40

CMMXCIV

CM + M + XC + II = 900 + 1000 + 90 + 4 = 1994

However I can tell you that the most common roman numerals used in

Pharmacy would be I, II, III, V, X, C .

Hope this helps you also.

Respectfully,

Jeanetta Mastron CPhT BS Chemistry

Founder/Owner

-- In , " alsobrook00 "

<alsobrook00@y...> wrote:

> If a dose for a drug is 12mg but the drug come only as a 3mg tablet,

> how many tablets are needed for the dose?

>

>

> A. 4

> B. 5

> C. 3

> D. 12

>

>

> 4 is to IV as 10 is to

>

> A. L

> B. M

> C. X

> D. C

[Guest guest]

le0014,

I assume you are asking for assistance in solving this problem, not just

posting it for practice.

Problem: How many 100mg tablets will be needed to make 1/2 liter of a 1:250

solution?

1st you have to identify the information in the problem.

1/2 liter = 500 mL

A solution in given in ration strength is " x " G/ " y " mL

1:250 = 1 G / 250 mL

Taking this further: 1 G = 1000 mg, therefore this also means 1000mg/250 mL

Next: You want 500 mL of solution, set up your ratio/proportion and solve

for X:

1000 mg/ 250 mL = X mg/ 500 mL

X = (1000 x 500) / 250 = 2000 mg

You have now identified you need a total of 2000 mg of drug to make your

solution.

You have tablets that are 100 mg / tab. Set up your ratio/proportion:

100 mg / tab = 2000 mg / x tabs

2000 / 100 = 20 tablets

Hope this helps,

Anne LaVance

Texpert

[Guest guest]

GREAT Job! Anne! I am not allowed on at work any more due to viruses that

we get from time to time. So I could not get to this earlier today. Just now got

home. Thank goodness for TEXPERTS! And for YOU!

Yes Leoo14 I concur with Ms La Vance.

I would lke to take this moment to expound a bit on the philosopy of this site!

I would like to call your attention and that of EVERYONE's on this site that I

have an educational goal and philosophy. And it includes TEACHING and giving

direction to someone to continue their education and to try various approaches

to learning. It means mentoring sometimes and tutoring sometimes instead of

teaching, and it means coaching and motivating and stimulating others not

necessarily giving an answer on a silver platter.

This site is dedicated to helping YOU and OTHERS (I am not singling you out here

!) LEARN how to solve problems, how to research to find information, how to

find and use tools to help you learn or perform a skill. This is NOT a learn how

to pass the exam, or cram for the exam site. IT''s MAIN goal is to PREVENT

medication errors and PROTECT Q.Public is so doing. That I give back to the

community freely, voluntarily without reservation or call to do so. AND so to

ALL the TEXPERTS!

What we EXPECT in return is the following:

1. Participation by YOU, the membersm, to post your questions that give you

trouble AFTER you have exhausted the tutorials and have used a study guidebook.

What we HOPE for:

1. Continued input AFTER you become a CPhT, and to HELP others here on this site

going through just what you are now.

Here's what fuels our fire and passion to continue to do what we do:

1. Any crumb of appreciation is a fume of energy to keep us charged. We

especially love seeing the new CPhT's behind the names of those who have

posted!

Here is what drives us crazy:

1. When members post questions without apparent previous study or just because

they want the answer 'now'.

Here is what drives us crazier:

1. NO Particiaption at all, a dead study period between exams.

2. NO return to the site to give back to the community, whether in support by

adding to the membership numbers (strength in numbers) or actually posting and

helping others after the exam.

3.. Rudeness

4. No Respect

What have you said or done to deserve this 'lecture'-----NOTHING! Just the

short pick of the straws !

So here is what I ask, the ONE step further when ever I can is to get the poster

to do another similar problem, after following the tutorial or posting that

shows you how to do it. And I hope then that you will post yoru answer RIGHT Oor

WRONG. In this way you learn from example (from Anne in this case) and you learn

by doing and you gain confidence to do the SAME type of problem ON YOUR OWN.

So here is another few problems for you:

Problem #1: How many 500mg tablets will be needed to make 2 liter of a 1:125

solution?

Problem # 2 HOW do you make the above solution???

Problem #3: How many 7.5 grain capsules will be needed for a dose of 500mg?

Problem #4 The above drug is used as a hypnotic or sleep aid. If the patient

does not like capsules and the doctor wants to dispense the above for 10 days;

how many 7.5 grain capsules will be needed if each dose will be 2 teaspoonsful.

How much solution will you mix? How will you mix it? What size container will

you need to dispense it in?

Okay take some time and then post your answers. It's okay to call uncle if you

try, so give it some thought and try to use the tutorials and your math skills.

Resepctfully,

Jeanetta Mastron CPhT BS

Founder/Owner

InstructorCPhT@... wrote: le0014,

I assume you are asking for assistance in solving this problem, not just

posting it for practice.

Problem: How many 100mg tablets will be needed to make 1/2 liter of a 1:250

solution?

1st you have to identify the information in the problem.

1/2 liter = 500 mL

A solution in given in ration strength is " x " G/ " y " mL

1:250 = 1 G / 250 mL

Taking this further: 1 G = 1000 mg, therefore this also means 1000mg/250 mL

Next: You want 500 mL of solution, set up your ratio/proportion and solve

for X:

1000 mg/ 250 mL = X mg/ 500 mL

X = (1000 x 500) / 250 = 2000 mg

You have now identified you need a total of 2000 mg of drug to make your

solution.

You have tablets that are 100 mg / tab. Set up your ratio/proportion:

100 mg / tab = 2000 mg / x tabs

2000 / 100 = 20 tablets

Hope this helps,

Anne LaVance

Texpert

[Guest guest]

can someone pls solve this problem.

You receive a prescription for FeSO4 100mg po TID x 10 days. You look

on the shelf and find a 473ml bottle FeSO4 220mg/5ml. Approximately

what total volume is to fill this prescription?

a) 50 ml

70 ml ,,,,,,,,,,,,,,,,,,,,,,,

c) 90 ml

d) 110 ml