Card Range To Study

29 Cards in this Set

This chapter is about learning how to convert from metric to apothecary to household so we don't kill nobody. Plus what?

how to convert equivilants WITHIN the same systems!

the big problem is grains.

some say 60 or 65 mg = gr 1.

But what does this book want us to remember?

60 mg = gr 1

what is converting?

1)changing from one equiv to another equiv within the same system

2) changing equivs from one system to another system

measurements made after a conversion leaves us with a ...

an approximation, not exact. so?

so there are certain equivs established to ensure continuity.

some points for the nurse in making conversions

Memorize equivilents is crucial!
What is a conversion factor?

1,000 mg = 1 g

thus is called a conversion factor.

another point is to follow basic math principles regardless of the conversion method used.
Which system uses decimals?
Which system uses fractions?

metric system uses decimals

apothecary system uses fractions

remember this !

metric systems, based on decimal points, are easy to convert b/t them from millis to megas by floating the decimal point right or left. Why can't you use this with apothecary or household evivilant changes?

apothecary & household doesn't use decimal points!

there are 2 rules in moving decimal points: what are they?

1) to convert a small to large, ÷ or move the decimal point to the left
2) to convert a large to a small, ∙ (mult) or move the decimal point to the right.

MEMORIZE THESE EQUIVILANTS!

apothecary to metric

m15 or 16 = ? mL

metric to apothecary

1 mL = m 15 or m 16

apothecary to metric

dr 1 (3i) = ? mL

metric to apothecary

4 mL = ? dr (3i) 3 means dram

household to metric

1 t (1 tsp) = ? mL

metric to household

5 mL = ? t (1 tsp)

household to metric

1 T (1tbs) = ? mL

metric to household

15 mL = ? T (tbs)

apothecary to metric

gr 15 = ? g

metric to apothecary

1 g (1,000 mg) = ? gr

apothecary to metric

gr i = ? mL

metric to apothecary

60 mL = ? gr

apothecary to metric

1 oz (ˆ3i) = ? mL

metric to apothecary

30 mL = 1 oz (ˆ3i)

apothecary to metric

1 pt (16 oz.) = ? mL

metric to apothecary

500 mL = ? pt

apothecary to metric

1 qt (32 oz) = ? mL

metric to apothecary

1,000 mL or 1L = ? qt

apothecary to metric

2.2 lb = ? kg

metric to apothecary

1 kg (1,000g) = ? lb

one of the easiest ways to make a conversion is using ...

ratio - proportion

written in colon format

Can be written in colon format or as a fraction when making the conversion

5 rules for ratio-proportion conversions:
1) state the know equiv. (from memory)
2) add imcomplete ratio on the other side of the equal sign, making sure the units are in the same sequence: Ex. ---->

mg : g = mg : g

same sequence here, right?

3) label all terms in the proportion, including x

ignore ...

these labels are ignored when multiplying or dividing
----------- --------

4) solve problem by using principles for solving ratio-proportions.

the product of the means = the product of the extremes

Ex 3 : X = 4 : 1

the extremes are 3 & 1
the means are X & 4

5) the final answer for X should be labeled w/ the appropriate unit of measure or desired unit.

like duh

Ex. 8 mg = ________ g

solution:
1) state the known equiv. first (put it on one side)
2) add the incomplete ratio,
make sure units in same sequence!!!
3) label all terms in the proportion, including x

1,000 mg : 1 g = 8 mg : x g
(known equiv.) (unkown)

(read 1,000 mg is to 1 g as 8 mg is to X g)

now do the math...means = extremes

x = 8/1,000

you see this equation:

8 mg = ____ g

what is the first thing you should notice?

that the conversion is going from smaller to larger, thus division or moving the decimal to the left.

whats the next thing you notice?

the units are going from mg to g, thus changing by 1,000 NOT 100 or 10,000, but 1,000.
This is a BIGGY!!!

What else do you realize looking at 8 mg = _______g ?

that you will have to move the decimal point to the left 3 places to complete this conversion 8 mg = 0.0008 g