Guest guest Posted July 29, 2009 Report Share Posted July 29, 2009 Hi, could you please tell me where you got the C1xV1=C2xV2 I understood the rest of the math. Thank you From: Jeanetta Mastron CPhT BS Chemistry <rxjm2002@...> Subject: Re: Math Date: Tuesday, July 28, 2009, 9:46 PM Dear Ana, Can someone please help me solve these two problems!!! 1)How much D70W 1000ml is needed to make a D12.5W 250ml? C1 x V1 = C2 x V2 D12.5W x 250ml = D70W x V2 12.5% x 250ml = 70% x V2 12.5% x 250ml = 70% x V2 70%--------- ----70% 12.5 x 250ml = x V2 70 44.64 ml = V2 Check: 12.5% x 250ml = 70% x V2 12.5% x 250ml = 70% x 44.64 ml 3125 = 3124.8 3125 ~ 3124.8 2)How much of a D20W 1000ml and D5W 1000ml is needed to make a D8.5W 400ml? For this I would use an alligation method I suggest tht you use my tutorial in the Files Section Folder # 5 for Tutorials and open to Math Only Tutorials then to the Alligation Tutorial This method uses a diagram that is best drawn on a word document. The HTML does not do well with this type of a set up. Let Me know how it works out for you. Jeanetta Mastron CPHT BS Founder/Owner > > Can someone please help me solve these two problems!!! > > 1)How much D70W 1000ml is needed to make a D12.5W 250ml? > > 2)How much of a D20W 1000ml and D5W 1000ml is needed to make a D8.5W 400ml? > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted July 29, 2009 Report Share Posted July 29, 2009 Hi Ana, A formula expressed like this one with different 'letters or symbols' was 'invented' eons ago and is used in the sciences 9particularly chemistry) and math. You could also use: %1 x ml1 = %2 x ml2 Concentration 1 x Volume 1 = Concentration 2 x Volume 2 You could call it A x B = A2 x B2 In math it may make better sense without units: 2 x 4 = 1 x 8 2 x 3 = 1 x 12 or even: 2 x 6 = 3 x 4 C1xV1=C2xV2 is something that I have used in my chemistry classes and in teaching pharmacy. Hope this helps you. Where in terms of a book? Well many review books may leave out the formula and just show the work. Others would include the formula. You 'just have to know it' applies here. Hope this helps Respectfully, Jeanetta Mastron CPhT BS Pharm Tech Educator Founder/Owner of this site > > Hi, could you please tell me where you got the C1xV1=C2xV2 I understood the rest of the math. Thank you > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted July 29, 2009 Report Share Posted July 29, 2009 Dear Ana, Again you would use the formula that you asked about in the last post: %1 x ml 1 = %1 x ml 2 2.5% 500ml= 8.5% x ml2 2.5% 500ml = 8.5% x ml2 ----------- ---------- 8.5%---------8.5% 2.5 500ml --------- = ml2 = 147.06 8.5 You can also use the top portion of an alligation I. I am in class and just finished a break and will get back to you on the other math question later tonight. Hope this helps. Jeanetta Mastron CPhT BS Pharm Tech Educator/Advocate Founder/Owner > > Could someone please help me with these 2 problems. > > 1)Aminosyn is an Amino Acid offentimes used in TPN orders to provide protein for cellular repair and growth. A Physician writes an order for Aminosyn 2.5% 500ml. You look on the shelf and have only Aminosyn 8.5% 1000 ml. How are you going to prepare this order using a sterile evacuated container? > > 2)What is the percentage strength of a 1:2000 epinephrine solution? > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted July 29, 2009 Report Share Posted July 29, 2009 Dear Ana, Your second question: " 2)What is the percentage strength of a 1:2000 epinephrine solution? " When doing these types of problems one must remember that USUALLY percentage in pharmacy means w/v or grams/100 ml So X% = X grams/100 ml or X gm/100ml We must also know that X% usually means or is = X grams so 5% = 5 grams/100ml However using the colons ( means over the number after the colon so 1:2000 means 1 gm:2000 ml or 1gm /2000 ml So what does 1/gm in 2000 ml equate to in percentage? 1 gm--------X gm ------- = ------ 2000 ml-----100 ml 1 x 100 ------- = X gm 2000 0.05 = X gm = 0.05% Answer: 1:2000 epinephrine is equal to 0.05% epinephrine Hope this helps you. Respectfully, Jeanetta Mastron CPhT BS Founder/Owner Copyrighted by Jeanetta Mastron CPhT BS Chemistry 7-29-09 > > Could someone please help me with these 2 problems. > > 1)Aminosyn is an Amino Acid offentimes used in TPN orders to provide protein for cellular repair and growth. A Physician writes an order for Aminosyn 2.5% 500ml. You look on the shelf and have only Aminosyn 8.5% 1000 ml. How are you going to prepare this order using a sterile evacuated container? > > 2)What is the percentage strength of a 1:2000 epinephrine solution? > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted July 29, 2009 Report Share Posted July 29, 2009 Dear Ana, Have actually tried these math problems? Does the book you are using actually show you how to solve them? This time, I want you to go to the file section and give it a " TRY " . Files > 5- Tutorial-1 & Study Information > S 8- Math Tutorials Only > 3. Basic Rx Math Concepts Conversion factors.doc 60 or 65 mg? Which one should I use? http://tinyurl.com/mvqo77 http://f1.grp.fs.com/v1/oP5wSvh81gncxAGjtts4sDZ4gvNWxE4WlFSzQYtPT8aMf3PyUaf\ 2jZT6kuI_bPNP04II78MSQmk-u9jH_gVP/5-%20Tutorial-1%20%26%20Study%20Information/S%\ 208-%20Math%20Tutorials%20Only/3.%20%20Basic%20Rx%20Math%20Concepts/Conversion%2\ 0factors.doc 1 grain = 60 or 65 or 64.8 mg Use the tutorials that show you HOW to do it and try to solve it, by yourself. Then come back to the site and post your answer. I will then let you know if you are correct or not. If it is not correct, then I will show you HOW to do it. FREE teaching! Wow! Can't beat that! Hope this helps! Jeanetta Mastron CPhT BS F/O > > You receive a prescription for Levothyroxine gr 1/200, but your bottles are in milligram strength. What is grain 1/400 equal to in milligrams? > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted July 29, 2009 Report Share Posted July 29, 2009 Dear Ana, Here is also a Tutorial on Conversions and HOW TO convert that you may like: Files > 5- Tutorial-1 & Study Information > S 8- Math Tutorials Only > 2. Conversion Factors > 2. How to Convert Tutorial - Metric System Conversion Factors.doc Review list of the metric conversion factors. Example of how to convert within the metric system Jeanetta Mastron CPhT BS Founder/Owner > > > > You receive a prescription for Levothyroxine gr 1/200, but your bottles are in milligram strength. What is grain 1/400 equal to in milligrams? > > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted August 9, 2009 Report Share Posted August 9, 2009 the answew is 18% coz: %(w/w): w/w x 100 phenol:3.6g glycerin:i6.4g total weight:20g therefore,percentage concentration of phenol becomes: 3.6/20 x 100: 18% > > Hi all > > Please help > > If 3.6g of Phenol is mixed with 16.4g of glycerin, what is the > resulting percentage concentration of Phenol? > > Thanks Manny > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted August 9, 2009 Report Share Posted August 9, 2009 Dear blesschimezie, Since this was orginally posted three people have solved it and posted their method of solving NiKa. Wed Mar 17, 2004 3:56 pmM essage #4895 of 17772 Jeanetta Mastron CPhT Fri Mar 19, 2004 12:38 am Message #4916 of 17772 and now yourself. All three were well done. So this brings me to ask you if you have a particular or specific question regarding this math problem? Respectfully, Jeanetta Mastron CPhT BS Pharm Tech Educator Founder Owner > > > > Hi all > > > > Please help > > > > If 3.6g of Phenol is mixed with 16.4g of glycerin, what is the > > resulting percentage concentration of Phenol? > > > > Thanks Manny > > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted September 6, 2009 Report Share Posted September 6, 2009 So how are you doing with your math now Ana? Jeanetta > > Can someone please help me solve these two problems!!! > > 1)How much D70W 1000ml is needed to make a D12.5W 250ml? > > 2)How much of a D20W 1000ml and D5W 1000ml is needed to make a D8.5W 400ml? > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted October 11, 2009 Report Share Posted October 11, 2009 We regularly ask Jan to do simple math problems. In school, she topped out with very simple long division (don't take that too seriously). Still, the school did a great job teaching .. only to be lost when it wasn't kept up in ensuing years. The thing we are trying to maintain is functional math .. i.e. good enough to get through life. This is a parameter which is important to independence and to not being cheated at the store or restaurant. Currently, her multipication is weak, but she is generally quick with sums and occasionally differences. These are thins we work on a little when in the car together .. i.e. Jan and either parent. Once concept we've worked on .. not sure how well it has taken .. but it is important, is approximate math. If you have a $ 3.26 owed, whether told to you by the clerk or by the display on the register, and you pay $ 20, roughly how much change should you get. The answer is between $ 16 and $ 17. If you get $7 back, you should complain LOUDLY. You don't have to know the exact sum/difference to know you've been cheated. Even if a person who can't deal with something more complicated than whole dollars can learn to protect themselves. Just one parent's opinion. Teachers have a much different one because they want accuracy. I want to provide help getting through life. Rick Quote Link to comment Share on other sites More sharing options...
Guest guest Posted October 11, 2009 Report Share Posted October 11, 2009 We regularly ask Jan to do simple math problems. In school, she topped out with very simple long division (don't take that too seriously). Still, the school did a great job teaching .. only to be lost when it wasn't kept up in ensuing years. The thing we are trying to maintain is functional math .. i.e. good enough to get through life. This is a parameter which is important to independence and to not being cheated at the store or restaurant. Currently, her multipication is weak, but she is generally quick with sums and occasionally differences. These are thins we work on a little when in the car together .. i.e. Jan and either parent. Once concept we've worked on .. not sure how well it has taken .. but it is important, is approximate math. If you have a $ 3.26 owed, whether told to you by the clerk or by the display on the register, and you pay $ 20, roughly how much change should you get. The answer is between $ 16 and $ 17. If you get $7 back, you should complain LOUDLY. You don't have to know the exact sum/difference to know you've been cheated. Even if a person who can't deal with something more complicated than whole dollars can learn to protect themselves. Just one parent's opinion. Teachers have a much different one because they want accuracy. I want to provide help getting through life. Rick Quote Link to comment Share on other sites More sharing options...
Guest guest Posted October 11, 2009 Report Share Posted October 11, 2009 Ah, hates the estimation problems, LOL. She's actually pretty good with addition, subtraction and multiplication, and learning division, but she wants to solve the problems exactly... I don't think she really understands why anyone would estimate if they could just follow the rules to do the problem! Many times I think " why do we bother, if she can do the math " and you have just answered my question.... there IS a functional, long term reason to learn this! This IS an important skill... at least I have a good reason to keep learning this! Thank you. , mom to (13), (11 DS), and Sammy (10) Rick Dill wrote: > > > We regularly ask Jan to do simple math problems. In school, she topped > out with very simple long division (don't take that too seriously). > Still, the school did a great job teaching .. only to be lost when it > wasn't kept up in ensuing years. > > The thing we are trying to maintain is functional math .. i.e. good > enough to get through life. This is a parameter which is important to > independence and to not being cheated at the store or restaurant. > > Currently, her multipication is weak, but she is generally quick with > sums and occasionally differences. These are thins we work on a little > when in the car together .. i.e. Jan and either parent. > > Once concept we've worked on .. not sure how well it has taken .. but it > is important, is approximate math. If you have a $ 3.26 owed, whether > told to you by the clerk or by the display on the register, and you pay > $ 20, roughly how much change should you get. The answer is between $ > 16 and $ 17. If you get $7 back, you should complain LOUDLY. You don't > have to know the exact sum/difference to know you've been cheated. > > Even if a person who can't deal with something more complicated than > whole dollars can learn to protect themselves. > > Just one parent's opinion. Teachers have a much different one because > they want accuracy. I want to provide help getting through life. > > Rick > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted February 1, 2011 Report Share Posted February 1, 2011 Thought I would pass on. This seems like a fantastic website for math http://www.khanacademy.org/ This is free and built by one man on a mission to reach as many people as possible in the world to teach them math from JK to University. He provides short video tutorials on-line regarding any math problem you can think of. Demi Quote Link to comment Share on other sites More sharing options...
Guest guest Posted February 1, 2011 Report Share Posted February 1, 2011 Thank you, thank you and thank you again.    Bonnye- Faith's mom     From: td232006 <td23@...> Subject: [ ] Math Date: Tuesday, February 1, 2011, 8:14 AM  Thought I would pass on.  This seems like a fantastic website for math  http://www.khanacademy.org/ This is free and built by one man on a mission to reach as many people as possible in the world to teach them math from JK to University.  He provides short video tutorials on-line regarding any math problem you can think of. Demi Quote Link to comment Share on other sites More sharing options...
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