Pharmacy Tech Math - Alligation tutorial
Alligation math is a little known short-cut used by pharmacy techs and pharmacy students. It's also known popularly in pharmacy tech school as tic-tac-toe math.
Here's the next steps in how to work an alligation:
( Cont'd from previous page )
Step #4
So, now the amounts of the differences you found become the "Parts" of the % directly across the grid from it.
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→ Parts of the 3% → Parts of the 1% |
Step #5
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On your paper, write Parts of ___% Then, Add up the total "Parts" |
Step #6
Now, take a look back at the question and look for the total volume needed.
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On your paper, to the left of number of parts, write the needed volume Then, A division sign |
Step #7
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Do the Math: Now, you've divided the final solution volume into "Parts". In this case, there's 125mL per part. |
Step #8
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Now, go back up to the "parts" and write the volume per part. The Answer: The question asked how much 3% to use. So, that's :1 part X 125mL = 125mL of the 3% |
Here's what your paper should look like when done
Now, go to:
Alligation Math II - additional explanation
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