Derivation of Loan/Mortgage Monthly Payment Formula

Physics Ninja looks at the derivation of the Amortization Formula used to calculate the monthly payment on a loan or mortgage

Пікірлер: 60

  • @user-rz5xm2be9k
    @user-rz5xm2be9k5 ай бұрын

    Thank you very much. Was looking for how the loan was calculated and only getting the formula everywhere. But your explanation clears it out. Thank you!

  • @watch7749
    @watch77493 ай бұрын

    You sir, are awesome! This is the BEST explanation I have come across! I don't know if its because loan sellers don't want to be super clear or if they just lack the math background, but I hadn't found any of their explanations to make sense. This made it crystal clear, and I feel so much safer knowing what I'm getting myself into!

  • @boredomgotmehere
    @boredomgotmehere10 ай бұрын

    What a wonderful and thoughtful explanation. You not only gave the superficial meaning but the contextual meaning by doing the heavy lifting of proving the geometry series. Super thankful.

  • @PhysicsNinja

    @PhysicsNinja

    10 ай бұрын

    Thanks for the comment. I appreciate it.

  • @EverApprentice
    @EverApprentice10 ай бұрын

    I've been looking for how this formula is determined all over the internet, and finally here it is!! Thanks for the amazing explanation.

  • @avankm774
    @avankm7742 жыл бұрын

    I cannot give the amount of likes that I want. This video made my night after a whole day looking for explanations on how to calculate this and also how to make the table for each month. Awesome video and keep up the good work, thank you!

  • @PhysicsNinja

    @PhysicsNinja

    2 жыл бұрын

    Thanks for the support!

  • @tomera79
    @tomera797 ай бұрын

    Thank you. Very clear and useful! I wish more tutorials on the Internet were like this one!

  • @fozzydare7987
    @fozzydare79875 ай бұрын

    I’m determined to understand this fully - it’s going to take more than one watch 😅 Thank you for your work

  • @PhysicsNinja

    @PhysicsNinja

    5 ай бұрын

    It probably took me 4-5 times

  • @EverApprentice
    @EverApprentice Жыл бұрын

    Great video. Clear explanation and Python demonstration on this prolonged question I have in mind. Thanks for that!

  • @wanghonghui1553
    @wanghonghui15532 жыл бұрын

    Sir, you are a treasure for our society!

  • @otis299
    @otis2992 жыл бұрын

    Love your videos! Just FYI, the dollar sign goes in front of a dollar amount e.g., $100.45 or $1M for one million dollars. The lesser used cent sign “¢” would go after the number and would be omitted in the presence of a dollar sign e.g., 99¢. Thanks for all you do!

  • @09blueumbrella
    @09blueumbrella2 жыл бұрын

    This was very helpful. Thank you!

  • @arielfuxman8868
    @arielfuxman886811 ай бұрын

    This makes so much sense. Excellent for us Mathematically oriented people.

  • @PhysicsNinja

    @PhysicsNinja

    11 ай бұрын

    Thanks for watching.

  • @prashantdahiya711
    @prashantdahiya711 Жыл бұрын

    Thank You for the same, brilliant explanation.

  • @woojin8369
    @woojin8369 Жыл бұрын

    Thank you for exploring your curioisty and your due dilligence! This was inisghtful :))

  • @fozzydare7987
    @fozzydare79875 ай бұрын

    I’m determined to understand this fully - it’s going to take more than one watch 😅 Thank you for your workI

  • @Kappy0001
    @Kappy0001 Жыл бұрын

    Very nice work! Thanks!

  • @makk3480
    @makk34809 ай бұрын

    just one line for the video: AMAZING EXPLANATION!

  • @PhysicsNinja

    @PhysicsNinja

    9 ай бұрын

    Thank you

  • @JAMYLIVES
    @JAMYLIVES2 жыл бұрын

    Wow! wonderfully explained. Thank you!

  • @PhysicsNinja

    @PhysicsNinja

    2 жыл бұрын

    Glad it was helpful!

  • @ramineslami6053
    @ramineslami60533 ай бұрын

    thank you so much. it was really clear and useful.

  • @arkleston3299
    @arkleston32996 ай бұрын

    Thank you for explaining this so well!

  • @PhysicsNinja

    @PhysicsNinja

    6 ай бұрын

    You're very welcome!

  • @blackblather
    @blackblather8 ай бұрын

    wonderful explanation. Thank you

  • @juant4821
    @juant4821 Жыл бұрын

    Excellent derivation!

  • @Epistemer
    @Epistemer Жыл бұрын

    Thanks man, great explanation :)

  • @patomatma
    @patomatma7 ай бұрын

    awesome job

  • @majid1885
    @majid18857 ай бұрын

    great video, thank you

  • @susovandey4531
    @susovandey45312 жыл бұрын

    Awesome brother

  • @bansheedearg
    @bansheedearg Жыл бұрын

    Thanks for sharing the python code, for python3, print() is a function so you'll have to wrap the strings in parens. Great video, thank you!

  • @gtrecc5454
    @gtrecc54549 ай бұрын

    Great video

  • @funnelboss5721
    @funnelboss57212 жыл бұрын

    Awesome Thanks for sharing, may i ask why simplify geometry part (2) - (1)?

  • @matteogriseri6513
    @matteogriseri6513 Жыл бұрын

    THANK YOU FINALLY

  • @user-fy4iq6if4z
    @user-fy4iq6if4z Жыл бұрын

    짱입니당

  • @b.c.2836
    @b.c.28365 ай бұрын

    Taking python class, already built a calculator for amortization total interest paid, but no wanted to bulid one that took into account extra principal payments and I was looking for that formula.

  • @adamidrisnuh4328
    @adamidrisnuh4328 Жыл бұрын

    Thank you... Very much appreciate. If my lecturer teach this formula, i think my financial management will get A.

  • @orionfollett7056
    @orionfollett70562 жыл бұрын

    Isn't dividing the annual interest rate by 12 to get the monthly rate an approximation? Going up 12% a year is not the same as going up 1% a month. Anyone can easily see this by just inputting it into a calculator if they don't believe me. (1+.12)^1 = 1.12 =/= (1+.01)^12 = 1.1268... I know this is how most calculators work still but I wonder why this approximation is always used?

  • @ScienceDiscoverer

    @ScienceDiscoverer

    Жыл бұрын

    I noticed this too... I guess its just because of the en.wikipedia.org/wiki/Time_value_of_money If you pay your loan in the end of the year in one payment, you will have to pay more, as all the payment will be in the future, thus it cost will be more than if you paid small sum every day or every month. You are still paying bulk of the loan in the future, but few payments in first month worth much more than those in the end, so the end interest sum is lower in this case, although the "annual" interest stays the same!

  • @ecolibertarian5622

    @ecolibertarian5622

    6 ай бұрын

    The assumption r=R/12 is never used in the actual derivation so the formula still stands. And you are right, r would be the monthly interest rate that translates to the R annual rate. i.e (1+r)^12 = R.

  • @CliffSedge-nu5fv
    @CliffSedge-nu5fv3 ай бұрын

    I've actually been looking for a derivation of present value given future value, but I think I can use this as a guide for how to set it up.

  • @cradleofrelaxation6473
    @cradleofrelaxation647311 ай бұрын

    Thanks. I was like how the heck did my back come up with the money payment?

  • @NeonCurveZz
    @NeonCurveZz2 жыл бұрын

    You got rid of the porsche? I thought you were planning on getting an R8 next?!

  • @youpattube1
    @youpattube13 жыл бұрын

    Thanks for the derivation. But...... And this may sound like something a flat earther would ask, but it seems like interest gets figured in twice. To get the Current Payment, you take the Prevous Balance, subtract the previous payment, and add the interest paid on the previous balance. But the interest was already figured in the monthly payment. I'm just a little confused.

  • @martincstee5335

    @martincstee5335

    Жыл бұрын

    This video explains it better: kzread.info/dash/bejne/pKh9pKmhkrbLcrw.html&ab_channel=DrBobMaths%28OnlineMathsTuition%29 Essentially the first month when you obtain the loan, you do not make any payment. The interest for the first month accrues at the end of the first month, regardless if you make the payment either at the end of the first month or the beginning of the second month. So, at the end of the first month interest was only factored in for the first month. At the end of the second month, interest was only factored in for the balance minus the first constant payment. One can argue that the constant monthly payment M already contains the interest Pnr. But at least for the first month the interest of P0r is correct. Maybe some math genius can derive a more logical formula that can save us all some interest payment.

  • @shivankagrawal9764
    @shivankagrawal9764 Жыл бұрын

    16:21 But why did you multiply X by (1+r)

  • @bansheedearg

    @bansheedearg

    Жыл бұрын

    So he could eliminate all the internal terms of (1+r)^n. If I have 1 + A + A*A + A*A*A + A^4 + A^5, I can multiply and divide by A - 1 to get (A^6 - 1) / (A - 1), or why he subtracted equation (2) from equation (1)

  • @Scott-jk5zk
    @Scott-jk5zk2 жыл бұрын

    18:26 how does (1+r)X-X=rX ?

  • @Scott-jk5zk

    @Scott-jk5zk

    2 жыл бұрын

    one sec X((1+r)-1) X(r+1-1) X(r) rX I see now

  • @NgocTruong-zt9dp
    @NgocTruong-zt9dpАй бұрын

    Bro can you explain why p1 = p0 -M +p0*r ?

  • @user-sm1fh1iy4p
    @user-sm1fh1iy4p9 ай бұрын

    Well i can explain this a little more simply. Just explain what annuities are and how it's formula is derived. Done!

  • @PhysicsNinja

    @PhysicsNinja

    9 ай бұрын

    Clear as mud!

  • @truthfirst9488
    @truthfirst9488 Жыл бұрын

    Is this for USA or Canada?

  • @TusharMajumdar
    @TusharMajumdar2 жыл бұрын

    Thank you very much. Was looking for how the loan was calculated and only getting the formula everywhere. But your explanation clears it out. Thank you!

  • @fozzydare7987
    @fozzydare79875 ай бұрын

    I’m determined to understand this fully - it’s going to take more than one watch 😅 Thank you for your work