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From: Tim Kurtz  (a.k.a. Prof. Maths - the original 'Dr. Math')
Subject: Professor Maths

You have done a nice job with the Math Forum and with Ask Dr. Math. 
My project has not been officially running for several years since I left the 
mathematics department at St. Bonaventure University.  My address lives 
on though, and I get several questions each week.  

I recently received a request for the name of the horizontal line in a 
fraction. Upon searching your archives, I came across an entry on the
same subject in which you shared the words virgule and solidus for the  
diagonal line.  It is used in the following ways:
         alternatives           and/or
         to mean "per"          miles/hour
and to delineate line breaks    Old King Cole/Was a merry old soul.

I shared this with the fifth grade student from Australia but I would like to 
address his real question.  What is the horizontal line called?  Got any 
ideas, or who to ask, or how to proceed? - Prof. Maths

[See the Dr. Math FAQ - Math Terms: "What do you call the 'fraction bar'?"]


From: Travis Johnson Subject: Thank you!! Thank you very much for your time and quick response! This is a great service for those of us who are "mathematically challenged"! I only wish I could repay the service.. - Kim Johnson
From: Anthony D. McKenzie Subject: Thank you Thank you so very much for responding to my question. You really helped me out a lot. My math teacher said that there was only one way to solve the problem in every situation. Your answer proved my math teacher wrong for once. Thanks again!
From: Tammy Goble Subject: Re: Complex Number Applications I greatly appreciate the time dedicated and information given in your response to my question about complex numbers. I never dreamed I would get such a thorough response. I was very impressed with your attention to detail. Thanks so much for the information!
From: timkey Subject: Re: Pre-algebra Doctor Mike, Thank you sooo very much! We checked the problems in pre-algebra and the answer that you sent me was correct. It was so simple that I was reading somthing that wasn't there. I really appreciate you taking the time to write me back. Off the subject do you have any kids that are my age that would like to correspond? I'm 14. Thanx ;)
From: Meenakshi Chauhan Subject: A special thanks Dear Doctor Allen, I am very very thankful to you. You replied back to my message the next day. I had never expected a reply so soon from you. I did my test very nicely, and hope to get good marks. Thank you very much, - Meenakshi Chauhan
From: Meghan R. Busse Subject: Thanks, Dr. Math! Dear Ken "Dr." Math - In April last year you answered a question about how to use latitude and longitude to calculate distances. This was exactly the question I needed an answer to today. I have included a little Excel spreadsheet that implements exactly your calculations, for your or anyone else's interest. I found the Dr. Math site by searching Yahoo!, and browsed around a bit. I have to say, it is a terrific idea, _extremely_ cool. Keep it up, and thanks again. - Meghan Busse
From: Todd Edwards Subject: Re: Square with same perimeter and area as a triangle Thank you so much for your thorough proof regarding my square/triangle problem. I can't tell you enough how happy I was to hear from you. I was really excited by this problem, but quite frankly haven't had a lot of time to try and solve it. It's exciting to know that a resource such as yours exists. I told all of my students about Dr. Math and have encouraged them to visit your Web site. I've used a good number of lessons from your site and have found them really great! Keep up the great work. You help me feel "connected" to a larger mathematics community - which is important for high school teachers! Thanks again, Todd Edwards Upper Arlington High School - Columbus, Ohio
From: Robert P. Herbst Subject: distances between points on a sphere Dear Ken, A big T H A N K S for your help making this information available. Your text with the solution was adaptable to my problem. I used the formula for determining distances between an entered home zipcode of a customer who was searching for available dealers within a specified driving distance of his/her home. A complete table of all zip codes comes with a lookup table listing the latitude and longitude of all the zipcodes. Interesting was my need to adapt the formula to radian measure as required by the hardware.A nice exercise. You're a good man to know. Will keep your address filed for future reference. Thanks again. - Bob Herbst
From: Andrew Sherk Subject: Rd: vector proofs and linear combinations Thank you Doctor Anthony for your most prompt response! I give Doctor Math many thumbs up! - Andrew
From: John S. Egan Subject: Re: Volume of water To Dr. Tom, The Math Forum I just wish to thank you for giving me the formula for figuring the volume of a sphere the size of our earth. I was unable to do the problem until tonight because I had to find out from my son how you work with such large numbers with the computer. It is really nice of you to offer this service and I surely do appreciate it. Thank you. Very truly yours, John S. Egan
From: Cheron Frazier Subject: Many thanks to you Dear Dr. Kate: Thank you so much for responding to our math problem so quickly. I actually sent the question in on behalf of my son, Julian (16 yrs), as he has this problem in his physics class and hadn't a clue as to how to solve it. When I first set us up on the web I bookmarked a whole library of reference sites, categorically arranged, i.e., math, science, etc., believing my teenagers would actually use the library if they didn't have to dig too deep for a starting point. Dr. Math was number one in the math folder, but they just weren't interested in checking it out. So, when my son came to me with this problem I took it as an opportunity to hop on line and e-mail your site with the problem while he was standing next to me. I just wanted to let you know how impressed my son is with the internet now because of you. I too am impressed by your clarity, in that I actually (almost) understand the concept of the problem now that you've explained it. Again, Thank you. - Cheron Frazier, San Marcos, California (P.S. Thanks to you, I think now my son views the net as more valuable than just someplace to try to "sneak" to XXX sites.)
From: Amanda Piedra Re: /dr.math/problems/cmplxjones.html I would like to take a minute to tell you that Dr. Math is the best thing on the Web. It helps me every time I have a question about something and don't want to ask my dad. You are the smartest bunch of people I've ever seen. Sincerely, Amanda
From: Richard White Subject: Geometry Page: /dr.math/problems/gameshow.html The cylinder in the sphere problem made its way into Ask Marilyn but her answer was really difficult to interpret. Your explanation is far clearer... Thanks. - rw
From: Kimberly Kirkpatrick Subject: Kudos, Dr. Math! I just wanted to congratulate you on a wonderful idea. Dr. Math is wonderful and I have a feeling we will see similar programs around the country in the near future. Good job!
From: Mr Basudeb Gupta Subject: Re: trigonometry Dear Dr. Math, I want to thank you for helping me in the tough mathematics problem. Following the method you had stated in your e-mail it took me very little time to arrive at the result. I appreciate your help and I will look forward to your guidance if I am in trouble again. Regards, Chitrak Gupta, Calcutta, India.
From: Nathan Chute Subject: Re: Thanks centroid of a triangle Thanks so much for such a speedy reply (4 hours). This is an example of the real reason there is the Internet.
From: G Schueler, Uni-Regensburg Subject: Test Lieber Dr. Math, Wir vom Goethe-Gymnasium in Regensburg schicken Ihnen GruBe!
From: Vern Klein Subject: The hole in the sphere math. oddity. To: Dr. Rob, The Forum. Thank you for the prompt and very good response to our question about the hole in the sphere and the constancy of remaining volume of the sphere! Now we understand the "problem" and see how the unspecified size of the sphere is actually dictated by the diameter of the hole one chooses to bore through it. Your ASCII Art was really quite good. It was certainly very adequate for me to make sketches to show my friend, Merilee. ... we're going to get involved in quantum mechanics concepts and neither Merilee nor I can clain much expertise in mathematics - we may be back to Dr. Math!... Again, thank you for resolving the hole-in-the-sphere problem for us! We won't spin our wheels on that one any more. May the new year be good to all of you there! - Vern and Merilee
From: Timothy Basaldua Organization: University of Illinois Chicago Subject: Great Place To Visit I'm 52 years old and find myself back in college struggling with mathematics. Thank god I have stumbled onto this site. Just reading the questions and your answers has already been a great help to me. Thank you again.
From: John H Dear Dr. Sarah: Thank you for your help on mean, median, mode. I think I can finish my homework before class today. I'm so glad I've found Dr. Math! Now I have a Math Buddy at my fingertips at home - very reassuring. - John H
From: Linda Hood Subject: dividing fractions Page: /dr.math/problems/janet6.7.html Thank you so much Dr. Math! I am a college student at Illinois State University in Normal Illinois. I am majoring in Elem. Ed and I ran into a problem that you helped me with. In my math methods class I have to explain why invert and multiply works when dividing fractions. I had no idea until I checked your website and there was an explanation. I'm so glad that you take the time to help people with their math questions (even college students!) Keep up the great work. - Linda Hood
From: Mervyn Hahn Subject: Re: Writing Linear Equations in Point-Slope and Standard Forms Dr. Keith - I would just like to thank you very much for the 4 pages that you wrote me on slopes. It really helped me out, and I appreciate all of the time you took to write it. Thanks! - Lauren
From: E. Chapman Re: /dr.math/problems/fractalsource.html Dear Dr. Math, You have never answered my questions directly, but you have helped my partner SO much with our geometry project! Thank you SO much! I was getting confused just trying to explain it to her!
From: LAWINE Subject: Re: division, rule for dividing by 7 Thank you so much for helping me with dividing a number by 7. Two of my other friends also needed to get this answer so they say thanks! I'll recommend you to all my friends!
From: Sebastian Leske Re: http://www.mathforum.org/about.forum.html I recently discovered the 'Math Forum' pages and I've been especially amazed at the loads of interesting questions and answers. I'm currently studying mathematics at a university here in Germany, but I never quite realized how many interesting problems there are even on the elementary school level. I can only congratulate you on your choice of problems and on the imaginative and well written solutions you provide!
From: Heather Foster Page: /dr.math/problems/fields3.29.96.html Hi - thanks for the help! I came to look for a common multiple and found out thanks to you, Dr. Math! Sincerely, Heather Foster
From: Vasha N. Rosenblum Subject: Re: request permission to share Thanks for the permission to share the Dr. Math site. The first presentation was a bit scary because I was using a zip drive (new hardware for me) and new software (WebWhacker), but it went off without a hitch. People were very enthusiastic about the information! Next presentation in Atlanta, Feb. 27... I like showing kids the site and looking at the kinds of questions people send in and what answers are given. It gives me ideas for problems to give my students, with some background info provided by "Dr. Math" that helps me ask appropriate questions to probe thinking. In other words, it teaches me some mathematics that supports my teaching. (Elementary teachers don't generally enter the classroom well prepared to teach math, and we need all the help we can get!) When I look at the archives with small groups of 2nd, 3rd, 4th, or 5th graders, they never want to stop! They clamor for me to click on one more topic to see what is there. The site serves to broaden their horizons from school math to seeing math as a rich, varied topic. ...It is very interesting to see what kids ask. There is a lot to be learned right there, since we assume they think in certain ways and their questions reveal quite a different story. Who would expect primary students to wonder who made up zero, or who invented the plus sign! I am so grateful for anyone out there helping teachers do a better job of teaching, that I'm not much good at thinking up ways to do it better! Swarthmore has done a super job of providing support for math at all levels. We also have just started looking at the POW. What a great idea to have visiting math mentors to share the work load of looking at the responses and posting solutions. Thank you! Vasha N. Rosenblum, Presidential Awardee Elementary Math '93 South Shades Crest School, Hoover, AL
From: Michael Barnes Subject: Love you guys Page: /dr.math/tocs/algebra.high.html I just want to thank you because I don't need help that much but when I do, no one can help me but you guys. Thank You a Bunch and I might need you again.
From: Jane Hicks Organization: Glenlyon-Norfolk School Subject: Thanks for the help! Many thanks for your help tonight with my sixth grade daughter's homework question- "what is an eleven sided polygon called?" Your site was found through the Internet Public Library site, and was also referred to in a recent article in the Vancouver Sun. She had been sent home with instructions not to ask her mother, me, a high school math teacher, and frankly, the magic of searching your site was just as good as finding the answer. After all, we all know that finding an elegant solution is the true beauty of mathematics! She tells me that the Ask Dr. Math site was as close to asking me as she could get. Many thanks for your help. By the way, my husband was very impressed that we were talking to The Math God, John Conway. Jane Hicks, B. Math '74, University of Waterloo
From: Harold Deskins Age: 22 Subject: Finally I really do not have a question. would just like to tell you guys what a great site you have here. I see many questions (both on your pages and in life) as to why math is important. I myself once thought that "I will never use this stuff." Now I wish I had paid closer attention in class during high school. As an Economics senior at Radford University, I find a greater use for math with every passing day. Whether it is integrals, statistics, or whatever, math plays a very important role in my studies. I just wanted to let you guys know that yours is the first page I have found that is so complete. I use this page often. It is interesting to go back and brush up on some of the things that I have forgotten as well as learn new things and applications from the questions of others. Again, I salute your efforts and it is very much appreciated. It is my opinion that yours is the best math related page on the net. Thanks, Harold Deskins
From: Debra Hope Subject: Re: geometry -Reply I am so excited! Thank you so much! It was my first time tracking you down. I had heard about you from other kids at school. I am in the 5th grade at PK Yonge Developmental Research School at the University of Florida. After sitting at the table fussing with Dad about who was right, (my dad thinks there are six edges on a cube and I think there are twelve edges - who is right?) we headed to the Internet! I was very excited to see a reply so quickly and the explanation is awesome. If that doesn't convince Dad I was right, nothing will! Thank you so much for being out there to help us kids. It is very exciting that so much is available to our generation through the Internet. Thank goodness for the computer nerds! Have a great day...hope to talk to you again! - Tyler Hope and my Mom who agreed with me.
From: Michelle Dombeck Age: 13 Subject: No question, just a big THANKS! Dear Dr. Math, I just want to take a moment to thank all you great people out there who dedicate your time to help out frustrated kids like me. Your great site has helped me more than once, and almost our whole math class uses your site to help us, too. I like the variety of questions you keep in your archives that save time for everyone. I hope you people continue to do this for a long time. THANK YOU! - Michelle
From: John Lesniak Subject: thanks Page: /grepform.html Yesterday I submitted a question on limits and factoring a polynomial that had been bothering me for several days. Your incredibly prompt response was highly appreciated. I haven't studied math in 25 years and thought I'd see just how much I've lost. So I went to the local library and checked out a textbook. There are a lot of gaps I have to fill. Your response was a clear as any I've ever received from a teacher, and I've had some good ones. Unfortunately, by the time I got into the heavy stuff at Cornell, they figured you were smart enough to digest it from a non-native English speaker. Not me. So I drifted into the "soft" social sciences and the rest is history. Thanks again!
From: student e8926506, Technische Universität Wien Subject: Ask Dr. Math Dear 'Dr. Math', Vienna, 97/05/06 We are students of Vienna's Universities running a private information page called Austria Information Switchboard. Every week we select one page from the mass of internet offerings for its information value. This means for our visitors they will find interesting and well presented information which are worth the time to spend a visit. Your pages on Math are the Information Value we have selected and introduced this week on Mai 03, 1997. You can visit the page at http://stud1.tuwien.ac.at/~e8926506/infoval.htm Congratulation for your good work. - Ed
From: Campbell Subject: Re: Math Logic Puzzle Hi Doctor Daniel, Thank you so much! I tutor Algebra students so I will be telling them all about your site! What a great place for our kids to come even when their mom who loves math gets stumped! Thanks again. - Debbie Campbell
From: DKTEDD Subject: Re: Converting cubic yards to sq. ft. Thanks very much for responding and broadening my basic math skills. It's great to see people still take the time to help other people. Again, thanks.
From: Denise Clevenger Age: Parent Subject: Thank you On April 29th, you e-mailed my son Justin back with the help he requested. As his parent, I just wanted to say God bless you! My son was able to finish his homework without it turning into a stressful situation for both of us. It is interesting to know that my son was the only student in that 7th grade math class who turned in his homework the next day. I am sharing our discovery (you) with my son's math teacher and his classmates. Thank you again, you're an angel.
From: Kazak2 Subject: thanks Dear Dr(s) Math, I am an engineer with a bunch of kids, and I typically teach a class for each of them once or twice a year. I was asked this time to teach multiplying and dividing fractions. I stumbled across your web site, and will be using some of your solved problems in my lesson. I'm used to dissecting frogs and building small bridges, and was concerned that this would be a mighty dry lecture. Your material will be a very big help. Thanks for your help, and for your commitment to educating kids. - Paul Stone
From: Adrienne Subject: calculus Let me preface my question with a sincere thanks to everyone who has helped me solve previous problems which I have submitted. I am actually beginning to grasp some of the concepts which I have inquired about, and I must dedicate that achievement to the help of your staff. Anyway, to get on with my question...
From: Scott Olendorf Subject: Re: Volume of cylinder, partially full, on its side Wow, that works great. I just entered that into my spreadsheet and produced a table with every 1/4 inch measurement and how many gals. That's probably the first time I every really had a need for geometry after college. - Scott Olendorf
From: M. DePinto Subject: Re: Geometry Thanks so much for the help. As a parent of three, this is a great resource. I'm surprised at how much I managed to forget - it can be difficult to help with homework once they advance beyond the basics! - M. DePinto
From: Cathy Subject: Volume formulas I really appreciate your help! As a home school teacher, I visit this site often. It has been a big help - sometimes I just get stuck! Thanks!
From: Monte Richardson Subject: Re: percentage of savings Dear Dr. Math: Thank you for the quick response to my question. Besides just answering a question you have reminded me of some math processes that I have forgotten over the years. The educational function has again been fulfilled. I will certainly keep you in mind for the next time that I get stumped. Thanks again - Monte Richardson
From: Alexander Chupachenko Subject: Thanks Hello Doctor Mitteldorf, Thank you very much for the description of x1 = x*cos(t) - y*sin(t) y1 = y*cos(t) + x*sin(t) formulas. Your information was really very useful for me and now I have no problems with those formulas. Thanks, Alexander.
From: Justin Subject: praise I think that what you are doing here is a great idea. I think that it will encourage people to do their homework even if they don't really know how to do it. Now, they have some one to ask besides their math teacher or a family member. Plus it is a great way to get the knowledge of the internet. I believe that it is, by the old saying, killing two birds with one stone. They are getting the answer(s) to their question(s) and exploring the internet. I would highly recommend this site to students and teachers. I commend you with a job well done! Keep on answering your questions.
From: Becky Smith Subject: Tesseracts and hypercubes Thanks so much for helping my student with some information sources for tesseracts on the Net. I'll keep this communication on file for future reference on this topic. Your site is a great place for, not only students, but teachers and media personnel to get mathematical information. Becky Smith, Media Coordinator, Hickory High School
From: Brown Family Subject: Re: Fibonacci Sequences\Numbers and Golden Ratio Thank you so much, you've helped me the most out of everyone that's replied to me on the Net... I greatly appreciate it. Now I can finish my assignment. Thank you once again, - Kevin.
From: Richard Stack Age: 9 Subject: Your Internet page My class just started to study fractions and I came across your Internet page. I think your page is really interesting and I thank you for setting it up.
From: Mark Robbins Subject: Linear equations I just wanted to thank you for a very excellent service. My sixteen year old son was having problems solving and graphing linear equations. Being an electronics technician myself, I have no problem solving them; unfortunately, there were specific ways in which he was required to solve them and techniques he had to understand such as standard form, y-intercept, etc. After my first session resulted in teaching him using a method he would not learn in class for two weeks, I knew I needed some help. Your service gave me the quick re-cap and enabled me to explain to my son in terms he was familar with. I got to the page that I used using Webcrawler: /dr.math/tocs/eq.gr.trans.high.html Thanks again, - Mark Robbins
From: FluxBurr Subject: A surveying problem Thanks for your incredibly fast response to my question. I am going to have to sit down and work at this a bit but I think I can get it from here thanks to your help. I really appreciate this.
From: Lettie Witt Subject: Factoring polynomials. (algebra) Dear Dr. Math, I am writing on behalf of and at the request of my granddaughter who wrote you on Sunday regarding 8 (!) problems that had her stumped. She currently has online access only through my account, so she asked that I let you know how much she appreciates your prompt and helpful reply to her algebra questions. She is doing some advance work this summer and had calculated she needed to complete 7 pages each day to finish before school starts in the fall, and these problems had her stymied. Upon receiving your helpful reply, she said she was on her way again. Again, many thanks for your prompt reply and complete assistance.
From: Markusis Subject: WOW! I don't have a question, but I think that what you are doing is great. In NY state we take a test at the end of the year called a "regents" exam. This one test determines if we pass or fail the course. Well, I have a math regents in 9 hours, and I really needed help with permutations and combinations, and you helped me. So I want to say thank you, and keep up the good work. =)
From: Kristen A Long Subject: Re: SAT Algebra Question Dear Dr. Daniel, Thank you very much for your time. It is reassuring to know that whenever I get really stumped on a math problem (especially in the summer and there are no available math teachers at my high school) I can ask someone who knows exactly what they're talking about. You are providing a wonderful service. Also, thank you for the SAT tips. I'll do my very best! Kristen Long
From: Lamont R. Chestnut Subject: Letter of Thanks Thanks for helping me renew my 10-year-old daughter's faith in finding answers to educational subjects on the Internet. Tonight we both were stuck on the proper way to add and multiply fractions. We have it down pat now. Thanks once again. Lamont R. Chestnut
From: Todd Lloyd Subject: Thank you for your help Thank you for your help. My 10-year-old daughter asked me a question about prime vs. composite numbers. Your answer was just the ticket. Thanks again. Todd Lloyd
From: Keir H. Larock Subject: THANK YOU SO VERY MUCH!! This is just a little note of extreme thanks. You have been both prompt and attentive, and I thank you for it. The world needs more people who take the time to help others. Thanks again, Keir H. Larock
From: Qx93aa Subject: WOW!!! I have been searching for someone or some program to teach me Algebra at the beginning levels for weeks now. I am so excited to tell you that for the first time I understood algebra or at least the first basic problem 6x (4 + 3) . Thank you.
From: Aimee Smith Subject: Fwd: what a cool place I'm a trig teacher who was out browsing and found your site. What a fantastic resource! My students are going to be deluged with printouts tomorrow to questions that I have forgotten to answer or that I have found absolutely fascinating. Wonderful job you are doing there!
From: EVELYN Subject: Thank-you for Dr. Math Dear Dr. Math, This is not a question, but a comment. I have been struggling with my daughter, who is in the 4th grade. She can do division in her head but struggles with the long division and putting it down on paper. Thanks to a teacher online - she sent me your link, and now with the graphics and step-by-step simple instructions I have found I do believe my daughter will be fine. I much appreciate your efforts to simplify the process so that children can continue learning. I am very grateful to you and will continue using this wonderful site very much in the future. EVE2158 (Concerned Parent)
From: Arthur A. Molitierno Subject: Thanks for the math formula Dear Dr. Math, As one who seldom uses mathematical formulae, I just wanted to thank you for the site and for the clarity of the illustration of how to figure percentage increases. It saved me from indicating my ignorance to colleagues and solved my problem. If I can understand the illustration, surely kids in the grade schools can too. Best regards to keep counting and figuring, Art - English Department
From: Tim Gibbons Subject: Friends across "The Pond" I need to say "thank you" for the third year running. I really just want to say I can't thank you enough for your time and effort and the very speed with which you responded again. It is so, so gratifying I'm genuinely moved. You don't know me from Adam, as we say - which means you have no reason to be so helpful and so generous, and there's nothing in it for you. These are controversial times when the Internet is creating so much adverse feeling. The privacies and sensitivities of people are so often abused by mischievous and sometimes evil people, hiding behind the anonymity of the computer. To be treated in so friendly a manner and to be given so much assistance on what many people would dismiss as a trivial matter, is positively uplifting. If this eulogizing of mine sounds rather excessive, I don't wish it to - you've transformed my mood - the better side of human nature is still out there, alive and kicking! And it's smiled on me when I asked it to. That's how you've made me feel... and I'm going to be telling everyone about it for the next few days, just as I did last year, and the year before that!

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