Unit conversion word problem: drug dosage | Introduction to algebra | Algebra I | Khan Academy

Future doctors and nurses out there, take note. This unit conversion word problem deals with converting drug dosage units, something that is commonly done in hospitals. Give it a try with us.

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[MrTbonge]

You made this WAY HARDER than it needed to be.

[lillynguyen]

This is a very confusing and complicated way to solve this question.

[monkeyes]

I've been teaching "Med Math" for almost 15 years and found dimensional analysis is more difficult for the majority of students to learn than simple proportions.  But you did a great job showing it here!

[AdhyaPranata]

1) Convert Patient Weight(kg) to lbs: 160.2761 lbs
2) Multiply Patient Weight(lbs) with dose from the doctor(5mg/lbs): 801.3805 mg
3) Convert the result to gram: 0.8013805 g
4) Multiply the result with 1/0.9 ml/g (instead of 0.9/1 to cancel the gram and get the result in ml): ml

[samyethio]

You made it to complicated! Convert the 72.7 to kilogram.. 72.7×2.2=159.49. Multiply it by 5mg 159.49×5 it is going to be 799.7 then just convert .9 gram to milligrams it is 900. Divided 799.7mg by 900mg/ml

[donberg]

Why mix metric units with the English system? The lb. in the denominator should be a converted mass to the metric system. Mixing metric with the old English System is something they do here in the states that should be stopped. Check out the engine I'm working on, some bolts are metric while others are English! I'm converting all day!

[lisapfadt]

Dimensional analysis - straight out of nursing school. It is tedious but works every time.

[gabriellediaz]

Thank God im not the only this was really all over the place

[FaiLovex]

Lol as soon as he started doing the conversion I paused the video to read the comments and check if anyone else thought it was confusing

[theinsanedreamer]

Good example of unit conversion, though it seems a shorter way (at least the way that seemed more intuitive to me when solving the problem before seeing your answer, Sal), would be:
- convert patient weight to lb. (72.7lb * 2.2)
- calculate total mg needed for patient (5mg * 180kg)
- divide mgs needed by mg/ml ratio (800mg / 0.9)

[erintheis]

This was made much more complicated than it needed to be.

[adfkjgvdjfvbdbvdkjvb]

..."just in case I'm the patient receiving the treatment..." ...lol!! there's a valid reason to do a vid ;)
as always, thanks for posting!

[theskeptic]

@donttellmethetime I am a nursing student and I work with nurses as an aide at my work, and I can tell you that yes depending on what you have on hand in the med room on the hospital unit, you may have to do calculations like this. What the doc writes might not necessarily match what you have in the med drawer in the med room as far as units etc goes

[franzbiberkopf]

It is not confusing at all, it is a step-by-step solution to understand the logic behind the analysis in an algebraic way.

[veronicabagby]

I think it would be best if you could present the written problem so we can just read it and you can just work it out. Writing it down yourself takes too long and causes confusion.

[Ndomoffable]

I am not a nursing student and appreciate the steps. If you already know how to do it, just do it and stop wasting my time reading your comments about how smart you are.

[aldekorea]

If you see the previous videos of his pre-algebra playlist you wouldn't be confused, moreover, you'd get everything clearer 

[Saanam]

Sal did a great job explaining step by step of conversion...that's how they taught us in Pharmacy school too ;)

[shaun_b]

I start med school in 2 months this Video helps a lot thank you bro🙌🙌🙌

[ladycoralee]

This was helpful when trying to support math remediation to older nurses. The younger nurses memorized formulas in school while older nurses had to do dimensional analysis (no short cuts were allowed).