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Allegation Medial

by Sandy
(Raleigh)

Example problem in the book:

Prepare 1/2 L solution of 70% alcohol from 50% alcohol and 95% alcohol

500ml x .7 = 350g

Here is the part I don't understand:

278 ml x 0.5 = 139g
222 ml x 0.95 = 211g
139 g + 211 g = 350g


I thought it would be:

15/35 x 350 = 150g of 50% alcohol
20/35 x 350 = 200g of 95% alcohol

Where does 278 and 222ml come from??????


Comments for Allegation Medial

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answer to question
by: Anonymous

222: 20 parts of 95%
277: 25 parts of 50%

Algebra
by: DVN

.5x + .95(500-x) = 350
.5x + (.95*500) - (.95x) = 350
.5x + 475 - .95x = 350
(subtract 475 from both sides)
.5x - .95x = -125
-.45x = -125
x = 277.78 = ~278

Therefore, 278mL of 50%, and (500-278=222)mL of 95% :)

Thanks!
by: Anonymous

That helps a lot!

Tic Tac Toe Allegation videos
by: Ana

These videos will help you to understand better these kind of questions. It's easy to learn but too long to explain to you in words/text.

Dose Calculation
by: Anonymous

Thank so much to your kindly instruction. It is sound great on these program for preparing Pharmaceutical Technician Test.

HI
by: MUSA

95% 20 PARTS
70
50% 25 PARTS
TOTAL 45 PARTS
WE NEED 500 ML OF 70%
SO
500/45= 11.11 FOR EACH PART
20*11.11=222 ML FROM THE 95%
25*11.11=278 FROM THE 50%

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