Solving Compound Interest Problems PLEASE READ DESCRIPTION:)

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  • Опубликовано: 2 янв 2025

Комментарии • 423

  • @profrobbob
    @profrobbob  12 лет назад +1

    @faaavalon You are very welcome. I am glad you found my video so helpful:):):) Thanks for the kind words.

  • @profrobbob
    @profrobbob  12 лет назад +1

    It is not a difference of your way or my way, you are seeing the power of round off error! If the entire expression is typed in a computer at once you get your answer. If you work out the problem in steps as I did, even going out quite a larger number of decimals, you will have some round off error. The high the powers, the more careful you need to be about rounding:) Thanks for watching and the comment!!!

  • @profrobbob
    @profrobbob  11 лет назад +1

    And THANKS Nick for saying so!...Thank you too for liking and subscribing...I appreciate the support and hope if you continue to like what you learn you will share my channel with others at school:D

  • @profrobbob
    @profrobbob  12 лет назад

    There are some who should retire...but there are a lot of us who still love what we do and that's why we do things like this...to help others who make the effort to help themselves:) Thanks for being one of those!!

  • @profrobbob
    @profrobbob  11 лет назад

    You are SO welcome! It is generally the motivated students that seek out extra help and I'm glad my channel is becoming one they choose to watch and learn from. I will be starting my 3rd year growing my RUclips channel soon and we hope someday to be one of the favorite math channel to watch..."If you can dream it you can do it"

  • @profrobbob
    @profrobbob  11 лет назад

    I'm glad to hear that I am your go-to RUclips teacher and my videos are helping you through your math course after all these years...good luck and CONGRATS to you for taking on the continuation of your education!

  • @austincopeland2776
    @austincopeland2776 9 лет назад +19

    I often question why I bought my textbook when I can just watch your videos, lol.
    I honestly learn more from you than my from my real-life teacher.

    • @profrobbob
      @profrobbob  9 лет назад +1

      +Austin Copeland thanks for choosing my channel to study with!
      Please help us grow by liking, subbing, supporting the ads and sharing this channel with others:D

    • @mrsomera2293
      @mrsomera2293 7 лет назад

      Austin Copeland is my answer true?

  • @profrobbob
    @profrobbob  12 лет назад +1

    I am so honored and excited about your comment:):):) I hope you do great in your PreCalc class and I am glad I can help ease the toture...haha. Even being compared to the long time RUclips video producers you mentions is high praise. THANK YOU THANK YOU THANK YOU! Please help me by spreading the word about my math channel to anyone else that could find them helpful.

  • @profrobbob
    @profrobbob  12 лет назад +1

    I hope my videos will be the additional help you need to ace those finals!! Thank you for the show of support and subscribing:) Please share with your fellow students as well...spread the word:D...thanks.

  • @profrobbob
    @profrobbob  12 лет назад +1

    Thank you for the kind words:) I am very glad you like the way I teach. I hope that my style of teaching and how I record my videos help to develop a nice viewership/fan base for my math channel. I really love to hear you are helping others based on what you learned from my videos too! Sorry you tried to type your comments twice. I am an active full time teaching, so I like to approve what is posted to avoid any issues with my job or students.

  • @profrobbob
    @profrobbob  12 лет назад +1

    That's awesome! Thank you for watching more of my videos and making a playlist of them. I really appreciate the support, my channel growth is dependent on viewers like you sharing with others:)...thanks again!

  • @profrobbob
    @profrobbob  12 лет назад +2

    It is so awesome that I get to try and help people all over the world with a small camera and a computer. I am very glad you liked my video. Thanks for watching:) I hope you do well in your studies.

  • @profrobbob
    @profrobbob  12 лет назад

    THANK YOU:) I am glad I could help. Making RUclips videos wasn't even my idea. I student said something about doing this last year. I wish I had started making these years ago. I wish you great success in your classes!

  • @profrobbob
    @profrobbob  11 лет назад

    Now that you have subscribed you will be able to pull up my channel and watch a new video every time you feel the need to be taught a new lesson:)...and if you share with all your friends and classmates you could start a study group together to watch my videos, and then I would be like your private teacher!
    Thanks for watching and supporting by subscribing....what are you waiting for?...go start sharing...LOL :D

  • @profrobbob
    @profrobbob  11 лет назад

    eh..emm...did not skim that far into the video...sorry. In the last example the variable is still in the exponent. You can solve the equation by applying the log of any base you like to both sides, common log base 10...Ln...log base 2 if you want, your final answer will be the same excluding round off error. I had just used the natural log on the previous question so I used it again. A time stamp in your question will ensure I answer your question correctly:) Thanks for watching.

  • @Danielsenreunion
    @Danielsenreunion 11 лет назад

    I've been out of high school for 13 years and I'm now having to upgrade my pre calc as I never took it when I was a student. My teacher rushes through all the units and I'm so great up that I can count on your videos to give me that extra bit of clarity on some of these complex concepts. Thanks a lot your my go to back up when I'm lost and you never disappoint. Keep up the good work.

  • @catherineelliotte7476
    @catherineelliotte7476 7 лет назад +2

    you're the only reason I'm passing business calculus in college so please, keep doing what you're doing- it's very appreciated!!!

    • @profrobbob
      @profrobbob  7 лет назад

      Thanks for studying and appreciating Catherine!
      Don't forget to sub and share this free study resource with your teacher so ALL future students might benefit like you did...BAM!!!

  • @profrobbob
    @profrobbob  12 лет назад +1

    You're welcome...and thank you for "liking" my videos, I appreciate the support and your viewership!
    (sorry for the delay but I have my channel set up to "approve" all comments before posting)

  • @profrobbob
    @profrobbob  12 лет назад

    @faaavalon Wow! I am so glad you found my video so helpful:):):) Thank you for watching. I appreciate your kind words very much.

  • @profrobbob
    @profrobbob  12 лет назад

    Thank you for noticing...and thank you too for subscribing:) Please continue to watch and learn and share my channel with your friends...thanks.

  • @profrobbob
    @profrobbob  11 лет назад +1

    THANKS for liking and subscribing…that's a great start! Keep watching and sharing my channel with all your friends and classmates and continue to help my channel groW to its full potential!!!

  • @profrobbob
    @profrobbob  12 лет назад +2

    Glad to see that the life-ring continues to be beneficial:)) So happy to hear that my video helped you so much...the info is out there, you just have to swim through the junk! Hope you will keep watching my channel and be sure to share with your friends if I've helped. Thanks:D

  • @profrobbob
    @profrobbob  12 лет назад

    thanks, and thank you too for subscribing...my channel growth happens through my subscribers and channel support:) Please spread the word and share my channel with your friends:D

  • @InSaiyanGames
    @InSaiyanGames 9 лет назад +2

    "BAM!!! that's compound interest!".... fucking love this guy

    • @profrobbob
      @profrobbob  9 лет назад

      +InSaiyanGames you're comment went into the "hold for review" because of the "F" word:(
      Thanks for watching...please like, sub and share:D

  • @profrobbob
    @profrobbob  11 лет назад

    You're welcome...and THANKS for supporting by liking and subscribing. (Sorry for the reply delay, I have my channel set to approve all comments to keep it viewable for ALL audiences:)

  • @MrUndergrounddweller
    @MrUndergrounddweller 12 лет назад

    You gotta be one of the greatest math teachers ever....you made this so easy and fun to understand. Wish there were more teachers like you.

  • @profrobbob
    @profrobbob  12 лет назад

    I worked my problem out in small steps and got some round off error. You have the more exact value...GREAT JOB. Sorry for the confusion:)

  • @profrobbob
    @profrobbob  12 лет назад

    And THANK YOU sir...I hope to see your "superpowazz" kick into overload after watching and learning from my videos:)) Please be sure to subscribe then you will stay current of all my new postings....thanks again for watching and supporting:)

  • @danielroy2100
    @danielroy2100 11 лет назад

    So... I am a student at Oklahoma State University and I must say, 9 times out of ten I come to your video lectures before I ever talk to my professor. You answer everything I need to know and keep it entertaining, well, as much as math can be I suppose. Thank you so much though!!! You should open an account for tips! I would love to pay you some for what you do! I know teaching is not the greatest of pay and someone like you deserves it!!!! Honestly!!! Thank you again!!!!!

  • @profrobbob
    @profrobbob  11 лет назад +1

    Thank you for your very nice comments, watching, and your support. I hope this all makes sense now:)

  • @profrobbob
    @profrobbob  11 лет назад

    Your answer is more correct than mine. I calculated my work in small steps to go over the order of operations in this problem and ended up with a bit too much round off error. Thank you for watching and commenting. Glad to see you are working the problems, that is the best way to learn:)

  • @profrobbob
    @profrobbob  12 лет назад

    THANK YOU:):):) I hope you do great in the math classes you have left in college. I tend to over explain as I teach and without the time constraints of a bell ringing....sometimes I go way overboard!!!

  • @profrobbob
    @profrobbob  11 лет назад

    Decay is when your base is between 0 and 1 and since you are talking about half life your base is 1/2 and growth is a base >1. So you have 16(.5)^#decay periods. Since your half life is 3.8 days you lose half in that number of days if you had a time period of 7.6 days you would go through 2 decay periods or 7.6/3.8=2. I hope this helps:)

  • @profrobbob
    @profrobbob  12 лет назад +1

    WOW...guess it was your lucky day huh?!...not only did you find T but you found
    (T)arrou's Chalk Talk to teach you...hahahahah:) Really, thank you for the comment and I'm glad you won't be bald for halloween!...(more bad humor, can't help myself sometimes) Thanks for watching and supporting:D

  • @profrobbob
    @profrobbob  12 лет назад

    I hate to hear you feel that way about your teacher...but I am glad you found my videos and liked them:) Anyone self-motivated to find outside help on their own will always succeed. Keep up the good work.

  • @profrobbob
    @profrobbob  12 лет назад

    Uhhhhh... Thanks:) I think I will just keep working on my videos so you can get the extra help when you need it! I am really glad you are finding them so helpful.

  • @profrobbob
    @profrobbob  11 лет назад

    Thanks for watching and subscribing Anna:)
    Please share my channel with all your friends too:D

  • @profrobbob
    @profrobbob  13 лет назад

    @xaqua93x You are very welcome:) I am glad I can help. I hope you find my other videos for Precalc helpful as well. Good luck in your class!

  • @profrobbob
    @profrobbob  11 лет назад

    You are so welcome! That's what I'm here for:) I hope you will continue to look to my channel for additional help and if you like it please support and subscribe and share the channel with others:D

  • @blasher4
    @blasher4 12 лет назад

    Straight forward and enjoyable. Teachers should take notes from you. This coming from a Sophomore in college. Thanks man.

  • @profrobbob
    @profrobbob  11 лет назад

    Interest rates are almost always based on a year, especially money. So when your money compounds monthly, you need to adjust the yearly percentage rate into what you are making per month so you have 10000(1+.07/12). The exponent is basically the total number of growth periods and there is 2(12) or 24 growth periods in 2 years.

  • @streetcones
    @streetcones 9 лет назад +36

    anyone watching this in 2015? This guy is dope

    • @profrobbob
      @profrobbob  9 лет назад +9

      David Durst I sure hope so!!!
      Thanks for watching and subbing!

    • @mrsomera2293
      @mrsomera2293 7 лет назад

      ProfRobBob is my answer truest

    • @aliceprytkova5845
      @aliceprytkova5845 5 лет назад

      How about 2019?

    • @crazyk2600
      @crazyk2600 4 года назад

      Almost end of 2020 here!

  • @profrobbob
    @profrobbob  11 лет назад

    First and foremost you have WOWED me with your compliments!...and you hit all the points. *To make math fun while learning, *To teach with explanation, and *To help students feel more confident with their work!
    I just made my new banner page, and because of multiple requests, added a "tip the teacher" link at the bottom right of the banner...does this mean that you can't see it where I placed it or you were not on my homepage? You're feedback would be appreciated.

  • @profrobbob
    @profrobbob  11 лет назад

    You take the ln(2) and then divide by .05. I did not enter the entire expression into my calculator at once and rounded off a bit too much. Ln(2)/.05 is approximately 13.863

  • @profrobbob
    @profrobbob  11 лет назад

    I am not sure where in the video you are referring to...other than there is 12 months in a year.?

  • @profrobbob
    @profrobbob  11 лет назад

    You are absolutely correct in that they are not equal. I was inconsistent with my rounding off in this video. My apologies.

  • @profrobbob
    @profrobbob  12 лет назад

    You are very welcome. I wish all my students would be willing to spend a day trying to solve their math problems!

  • @ItachisOkami
    @ItachisOkami 11 лет назад

    Thank you SO much! I was having such trouble with this. Must be good to see that your teachings are still being implemented by students willing to learn. Keep up the awesome work and thanks again!

  • @profrobbob
    @profrobbob  12 лет назад +1

    Thank you...always nice to hear MATH and FUN in the same sentence! Thank you for supporting my channel and if you like it be sure to share with your friends:))

  • @profrobbob
    @profrobbob  11 лет назад

    You usually need logarithms to solve an equation when the variable is in the exponent. Since the base of the exponent is e using log base e, or the natural log (ln), saves me a step because it quickly cancels with the base e.

  • @sciencegirl2012
    @sciencegirl2012 10 лет назад +1

    You seriously have the best handwriting that I have ever seen!

    • @profrobbob
      @profrobbob  10 лет назад

      THANKS sciencegirl2012 ...I even have a video teaching that:)...lol

  • @gg_loveh
    @gg_loveh 8 лет назад +1

    This video is from 2011 and I'm watching in 2016 and this was soooo much more helpful than my teacher could ever teach :))

    • @profrobbob
      @profrobbob  8 лет назад

      +Giselle Gomez thanks for watching...the only thing that's changed since 2011 is the color of my hair...lol

  • @RaphaelTeixeira-mi5sn
    @RaphaelTeixeira-mi5sn Год назад

    The best and most clear math from youtube. Great video and i was able to learn so fast

  • @nevillejohnson5811
    @nevillejohnson5811 12 лет назад

    EXCELLENT...Spent almost a day on a problem like this, my teachers method of solving it was too complex, dis s a much simplified and easy method...Thanks so much

  • @profrobbob
    @profrobbob  12 лет назад

    Thank you...I can never hear comments like yours too many times!!! I really appreciate you taking the time to send such a heartfelt comment:)) It's people like you that keep me motivated to continue my job...teaching can feel thankless at times but you reenforce the reason why I choose this as my profession. Keep watching and be sure to share my channel with your friends.

  • @AntoinetteAcosta
    @AntoinetteAcosta 12 лет назад

    You're teaching makes me feel so confident in mathematics/finance!! thank you!

  • @profrobbob
    @profrobbob  11 лет назад

    Thank you for seeking out extra help and choosing me to be your RUclips math teacher! Now that you have subscribed I too look forward to you continuing your math education with the help of Tarrou's Chalk Talk:D
    I hope you're feeling better now too =)

  • @profrobbob
    @profrobbob  11 лет назад

    Thanks for noticing...it helps to keep down the questions too:)

  • @profrobbob
    @profrobbob  12 лет назад

    Thank you for pointing that out. Round off error is always and issue to be aware of:)

  • @georgesadler7830
    @georgesadler7830 2 года назад

    Professor RobBob ,thank you for explaining and solving Compound Interest Problems in Precalculus/College Algebra. Once again, this topic is well known throughout Mathematics and the Invesment/Bank World.

  • @profrobbob
    @profrobbob  12 лет назад

    That sounds like a very good idea. This upcoming school year will by my second time through with my new math channel. I definitely need to fill in some gaps and redo a few videos:)

  • @Tyrendeth
    @Tyrendeth 10 лет назад

    Appreciate the videos! This is really something I wish I would have paid more attention to at a younger age. To anyone here in the younger crowd pay attention to this! It's probably the most important things you will learn in high school.
    I skimmed through in school to pass this class and I regret every minute of it. Now I'm here at 30 relearning what I'm kicking myself for not nailing down to begin with. Don't be me!

    • @profrobbob
      @profrobbob  10 лет назад

      And I appreciate you sharing the "words of wisdom" John Flynn !
      I think after a certain age we all wish there was something we had done differently but admitting our mistakes and sharing our life lessons is one way to "pay it forward" if one takes the opportunity to use them:)
      Thanks for watching and subbing and best of luck on your new math journey...hope my videos continue to be beneficial for you:)

  • @profrobbob
    @profrobbob  12 лет назад +1

    I love what I do and my mission is to try to "Make Math FUN!" while learning...so thank you for watching!

  • @profrobbob
    @profrobbob  11 лет назад

    That is compound interest compounded weekly, so p=1000,r=.03,and n=52.

  • @treblemaker3512
    @treblemaker3512 10 лет назад +3

    I love your handwriting... you're so good at writing on chalkboards! Haha, really great video too

    • @profrobbob
      @profrobbob  10 лет назад

      THANKS...19 years of experience makes it easy:)

  • @Kanaiza02
    @Kanaiza02 12 лет назад

    I like your energy I wish teachers would know and understand that teaching styles influence comprehension as well, keep it up, I have never done compound math’s but I learned a lot from your video and yesterday I though a math’s student one thing or two about compound, I am going to teach her once more today from the video, this is also my first youtube interaction from SOUTH Africa

  • @25sweetspicy
    @25sweetspicy 10 лет назад +2

    Math really makes me anxious and depressed... but your videos really made it more enjoyable for me. Thank-you.

    • @profrobbob
      @profrobbob  10 лет назад

      You're welcome...and THANKS for choosing Tarrou's Chalk Talk to help teach you math and learn to enjoy it:) Also, thanks for subbing!

  • @profrobbob
    @profrobbob  11 лет назад

    Wrap 13/9 in parenthesis and the exponent of 1/540 in parenthesis and I think you will be fine. 180 compoundings per year?

  • @jodiestatham2916
    @jodiestatham2916 11 лет назад

    Thank you so very much! This was by far the most helpful video that I found for compound interest.

  • @24Adrian24
    @24Adrian24 12 лет назад

    Sir, may I suggest you start making some word problems with logs. I think application to real world activities really deepens the concept. Thanks and appreciate your hard work!

  • @profrobbob
    @profrobbob  13 лет назад

    @xaqua93x I didn't mean to remove this!!!

  • @julijamozina3013
    @julijamozina3013 11 лет назад

    oh my goodness, I have been scrounging videos for this...and then I come across your video...I cannot tell you how clear you made everything! *subscribe!

  • @manoesko2615
    @manoesko2615 9 лет назад +3

    Nice step by step this really recommended for the beginners

    • @profrobbob
      @profrobbob  9 лет назад

      mano esko thanks for watching!

  • @profrobbob
    @profrobbob  11 лет назад

    My round off error was not on purpose and it has caused a couple of questions, but it shows how important what decimal you round to is:)

  • @profrobbob
    @profrobbob  12 лет назад

    Because I worked the equation in steps, there is round off error which you don't get when you type the equation in all at once.

  • @AntoinetteAcosta
    @AntoinetteAcosta 12 лет назад

    *Your teaching makes me feel so confident in mathematics/finance!! Thank you! P.S. audio sounds great to me.

  • @profrobbob
    @profrobbob  12 лет назад

    BAM!:))...One more to add to my captive audience, thank you!
    And remember, as a subscriber you will be notified of all my latest downloads. Spread the word if continue to find my channel helpful...thanks.

  • @christianalvarez6420
    @christianalvarez6420 9 лет назад +1

    Thank you so much. I really needed this for my test. I think my grade will go up now. Subbing to you. You're awesome bro!

  • @profrobbob
    @profrobbob  12 лет назад

    Do you want to find your monthly interest rate if you know the yearly rate the bank advertises?

  • @profrobbob
    @profrobbob  13 лет назад

    @delenabangel You are welcome:) ...and thanks

  • @MsPopperson
    @MsPopperson 9 лет назад +1

    Subscribed. Your enthusiasm is so perfect

    • @profrobbob
      @profrobbob  9 лет назад

      +MsPopperson THANKS for watching and subbing!
      Please continue to share my channel with all your friends and tell them to sub and do the same to help the free educational channels they find helpful:D

  • @nunabsnais
    @nunabsnais 10 лет назад +3

    Your energy and excitement make me laugh. :) I think MCC might owe you some money since I'm using your videos a lot as I'm taking an online algebra course. Feel free to send them your bill (but don't tell them I said so...I still need credits). LOL

    • @profrobbob
      @profrobbob  10 лет назад +2

      Thanks for choosing my channel to learn from, like and sub!
      In leu of a bill maybe you could just tell MCC to share my channel as a free resource tool for their students:) Then you get all the CREDITs...lol:)

  • @dimrostnimrodel9453
    @dimrostnimrodel9453 11 лет назад +8

    Love the end, "You learned some math."

    • @profrobbob
      @profrobbob  11 лет назад +3

      Thanks for watching & subscribing! I really appreciate the support and hope you did "learn some math!!!"

  • @elijahlondon3080
    @elijahlondon3080 7 лет назад +13

    2017???

  • @Wolfie1_
    @Wolfie1_ 11 лет назад

    great video!!!! ive been absemt a lot the last few weeks. sick. and all your videos really helped me catch up. thanks and I look forward to future videos .

  • @patrickstar1a6
    @patrickstar1a6 10 лет назад +1

    It is that simple!! :D
    Thank you! You saved me from going into an exam without understanding this. :)

    • @profrobbob
      @profrobbob  10 лет назад

      You're welcome DeadWolf and thanks for choosing Tarrou's Chalk Talk to learn from:)
      I hope you'll SUBSCRIBE and return whenever you need FREE math help:)

  • @profrobbob
    @profrobbob  11 лет назад

    You need to wrap you exponent in parenthesis. You are raising 1.67 by a power of 1 and then dividing by 120, not raising 1.67 by a power of (1/120)

  • @profrobbob
    @profrobbob  12 лет назад

    haha...that is embarrassing. I always say I teach math and not english but that is just bad! I can't always talk, think, and write at the same time. Thank you very much for watching and correcting me:)

  • @profrobbob
    @profrobbob  11 лет назад

    Did you figure out the answers? Sorry I just saw your question, though I don't know how to answer these.

  • @iLL1337
    @iLL1337 12 лет назад

    Thanks for making this video. I just wanted to point out something out, if you type the entire first equation into a scientific calculator using the fraction (.07/12) you get $40387.39... Your rounding of the decimal slightly skews the answer. Probably worth noting in the video. But thanks for making me think!

  • @nickhunter3334
    @nickhunter3334 11 лет назад

    Your students = Lucky kids my friend.
    Thanks for the lesson and the enthusiasm!

  • @JessZlovesmusic
    @JessZlovesmusic 9 лет назад

    I love your videos! You are a life saver!!! So if continuous compound interest were to triple, would we do what you did in the second to last example?

  • @tamiratayele7828
    @tamiratayele7828 4 года назад +1

    Excellent

    • @profrobbob
      @profrobbob  4 года назад

      Thanks!
      Don't forget to sub and share too:D

  • @jcemerson9804
    @jcemerson9804 7 лет назад +2

    This video is a life-saver

    • @profrobbob
      @profrobbob  7 лет назад

      BAM!!!
      Thanks for watching..please sub and share too:D

  • @kaseya7751
    @kaseya7751 10 лет назад +4

    wow you have really good handwriting and you explained that really well thank you now I know what I was doing wrong :)

    • @profrobbob
      @profrobbob  10 лет назад

      I have a video teaching my writing too...lol
      Thanks for watching and learning Kasey A please like, SUBSCRIBE, support the ads and share my channel with others if you continue to find it helpful because that's how I groW and help more students learn "what they were doing wrong"!

  • @roadtoad3484
    @roadtoad3484 8 лет назад

    at 14:18 I believe you did a rounding error. the answer is 13.86 =t doesn't that round up to 13.9. I don't think it matters all that much but I figured I would say something anyway. I am also super grateful for theses videos.

  • @alexmartino5949
    @alexmartino5949 9 лет назад

    Hey Prof Rob Bob,
    Thanks for the video. Out of curiosity, why does the exponent drop when you cancel out the e? Is there a rule for why you do that?

  • @jag959
    @jag959 12 лет назад

    What would be the raw formula to determine "r"? I am trying to implement such a formula into a computer program. Thanks for your time.

  • @profrobbob
    @profrobbob  13 лет назад

    @delenabangel 9300=5100(1+.01/4)^(4t).....1.824=1.0025^(4t).....ln1.824=4t*ln(1.0025)....ln(1.824)/(4*ln(1.0025)=60.178 years.

  • @helloitserica
    @helloitserica 12 лет назад

    My teacher makes me feel dumb. Your videos make me feel smart. Therefore, I chose to learn from you.