Hey there, just need help with these two. I need someone to help explain them to me/break them down.

Question

1. gr 1/100=_____mg

Answer: 0.6

2. 0.3mg= gr_____

Answer: 1/200

3. gr iii /ss= ______mg

Answer: 210

Thank you in advance!
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REPLY:

I did not get these answers. These are the answers from a packet I was given. It's for a nursing/dosage calculations class. It's to help us practice for the class. I am just as confused as I got the same answers as you did, Reiny. The last one has me just as baffled, I wrote it just as it is in the packet. Anyone else can help?

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Math - Ms. Sue, Saturday, June 4, 2016 at 6:14pm
1. No
2. Yes
3. ??

Math - Reiny, Saturday, June 4, 2016 at 6:15pm
How did you possible get those answers?
You are dealing with the simple metric system, so everything is simply multiplying or dividing by multiples of 10, the significant digits don't change.

1 g = 1000 mg
so (1/100) g = (1/100)(1000) mg = 10 mg

#2
1 mg = (1/1000) g
so .3 mg = (1/1000)(.3) = .0003 g

#3
gr iii /ss= ______mg ----> I haven't got a clue what that means.

Answer 1

you are dealing with the apothecary system. It is rare to be used nowdays.

1 grain=60 mg

1 gr iii/ss to mg means (from the latin) three grains and a half(ss).
3*60mg + 1/2 (60)=210mg

.3mg=.3/60 gr=1/200 grains

Most hospitals forbid MDs from using the apothecary, and household system (tsp, T, cup, oz, pint, lb) when writing med orders.

I wonder if Med schools still teach the apothecary system. I see grains is still on aspirin and Tylenol boxes, for what purposes I do not know.

Answer 2

Thank you, thank you! I have never heard of that system. But will continue this packet with that system in mind!

Answer 3

Thanks Bob for clearing that up.
I was curious and checked some of my bottles of Tylenol etc, none of them up here in Canada have units such as grains, it is all in mg.