# Calculation help..

1. Here's the problem:
Ordered: Morphine Sulfate 5 mg
Available: Morphine Sulfate gr.1/6 per mL.

Normally, I convert the fraction to a decimal because I don't like working with fractions, but this problem isn't working out for me either way. Can anyone help me figure this one? The answer key says 0.5 mL
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Joined: Jul '09; Posts: 193; Likes: 80
LTC/Skilled Nursing/Rehab; from US
Specialty: LTC/SNF

3. Are you forgetting to convert the grains to mg? 1grain=64.79891 mg
4. That is correct. I convert the gr to mg. So I say there is 60mg/1gr so there are Xmg/.17gr (6/1=.166). That gives you 10 mg. Then do D/H*V. So 5/10*1=.5. Hope that helped. I am so bad at math but for some reason calculation clicked with me. Good Luck!
5. Nursing Math - Medical Dosage Equations Formulas Calculators Examples Solutions For Nurses
http://www.davesems.com/files/drug_d...lculations.pdf
DosageHelp.com - Helping Nursing Students Learn Dosage Calculations

Medical Metric Conversion Tables and Dose Data
 [FONT=Arial, Helvetica, sans-serif]1 pound (avoirdupois) [FONT=Arial, Helvetica, sans-serif]= 453.592 g [FONT=Arial, Helvetica, sans-serif]1/2 grain [FONT=Arial, Helvetica, sans-serif]= 30 mg [FONT=Arial, Helvetica, sans-serif]1 pound (apothecary) [FONT=Arial, Helvetica, sans-serif]= 373.242 g [FONT=Arial, Helvetica, sans-serif]1/4 grain [FONT=Arial, Helvetica, sans-serif]= 15 mg [FONT=Arial, Helvetica, sans-serif]1 ounce (avoirdupois) [FONT=Arial, Helvetica, sans-serif]= 28.35 g [FONT=Arial, Helvetica, sans-serif]1/8 grain [FONT=Arial, Helvetica, sans-serif]= 8 mg [FONT=Arial, Helvetica, sans-serif]1 ounce (apothecary) [FONT=Arial, Helvetica, sans-serif]= 31.10 g [FONT=Arial, Helvetica, sans-serif]1/12 grain [FONT=Arial, Helvetica, sans-serif]= 5 mg [FONT=Arial, Helvetica, sans-serif]15 grains [FONT=Arial, Helvetica, sans-serif]= 1 g [FONT=Arial, Helvetica, sans-serif]1/100 grain [FONT=Arial, Helvetica, sans-serif]= 600 mcg [FONT=Arial, Helvetica, sans-serif]10 grains [FONT=Arial, Helvetica, sans-serif]= 600 mg [FONT=Arial, Helvetica, sans-serif]1/150 grain [FONT=Arial, Helvetica, sans-serif]= 400 mcg [FONT=Arial, Helvetica, sans-serif]7 1/2 grains [FONT=Arial, Helvetica, sans-serif]= 500 mg [FONT=Arial, Helvetica, sans-serif]1/200 grain [FONT=Arial, Helvetica, sans-serif]= 300 mcg [FONT=Arial, Helvetica, sans-serif]5 grains [FONT=Arial, Helvetica, sans-serif]= 300 mg [FONT=Arial, Helvetica, sans-serif]1/250 grain [FONT=Arial, Helvetica, sans-serif]= 250 mcg [FONT=Arial, Helvetica, sans-serif]1 1/2 grains [FONT=Arial, Helvetica, sans-serif]= 100 mg [FONT=Arial, Helvetica, sans-serif]1/300 grain [FONT=Arial, Helvetica, sans-serif]= 200 mcg [FONT=Arial, Helvetica, sans-serif]1 grain [FONT=Arial, Helvetica, sans-serif]= 64.79891 mg [FONT=Arial, Helvetica, sans-serif]1 kilogram [FONT=Arial, Helvetica, sans-serif]= 2.2 pounds [FONT=Arial, Helvetica, sans-serif]1 pound [FONT=Arial, Helvetica, sans-serif]= 0.45 kilograms (kg) [FONT=Arial, Helvetica, sans-serif]1 stone [FONT=Arial, Helvetica, sans-serif]= 6.35 kg [FONT=Arial, Helvetica, sans-serif]1000 mcg [FONT=Arial, Helvetica, sans-serif]= 300 to 7000 iu (below) [FONT=Arial, Helvetica, sans-serif]1000 mcg [FONT=Arial, Helvetica, sans-serif]= 1 mg [FONT=Arial, Helvetica, sans-serif]1 scruple [FONT=Arial, Helvetica, sans-serif]= 1.2 g [FONT=Arial, Helvetica, sans-serif]1 drachm [FONT=Arial, Helvetica, sans-serif]= 28.8 g
6. There are roughly 60mg in 1 grain. 1/6th of 1 grain would be 1/6th of 60mg 1/6 of 60 is 10. therefore, the concentration is 10mg/ml. For 5mg, you need half of that 10mg in 1ml, or 0.5ml.

<rant> And when are these nursing schools going to realize that no one uses grain, drams, minims, or avoirdupois ounces any more? </rant>
7. Thank you so much!! That helped tremendously! I glide right through these calculations until they trip me up with that stupid apothecary system. I'm so glad it's not used much!