Simple Interest Bi-Weekly Mortgage

  

Categories: Mortgage

Other than giving us discounts at Ross, what are percents good for?

Well, we don't always have to spend money to save it. Instead, we can make an investment or tuck it away into a savings account. Banks and investors actually pay us to do this by offering interest rates, usually given as—you guessed it—percents.

The amount of interest we earn, I, depends on four factors:

- the principal, P
- the interest rate, r
- the time, t
- how often the interest is compounded

The principal is the original amount of money you put into the loot. Whether you deposit $30 into a savings account or invest $500,000 in your cousin's startup company, that's the principal. Just to be clear, we aren't talking about your principal, Mrs. Lipschitz.

The interest rate is the percent of the principal that you earn. The higher the interest rate, the more money you'll earn. (Note: this is the opposite when taking out loans. Loans with high interest rates mean you'll have to pay more money back. It's a good lesson in context.)

The time we're talking about is the amount of time you let your investment simmer. The more time you leave your savings alone, the more you'll have saved up. (On the flip-side, the longer you leave your debts and loans unpaid, the more you'll owe in the long run.)

Compounding interest means adding the money you've earned from interest to the principal amount. It's a good thing for savings (but a bad thing for loans) because the interest rate will be applied to a larger balance. Basically, it means you'll earn (or owe) more money...faster.

We won't get into compound interest here, because that can get real complicated real fast. Instead, we'll talk about simple interest, or the amount of interest you can earn from the principal alone. That's right, Mrs. Lipschitz. Put down those knitting needles and pay up.

We can use a simple formula to calculate I: the interest you earn. If we know the principal P, the interest rate r, and the time t, all we have to do is multiply these three values together. As a formula, it looks like this:

I = Prt

When plugging values into the equation, it's a good idea to check for a few things. Our interest rate r should be in decimal form. Since percents are out of 100, it's easy to convert them into decimals. The interest rate and time need to have the same units. If you get 4% interest every month, you'll want to multiply that by the principal and the number of months you've had your investment, even if it's been 30 years.

Don't stress about calculating simple interest. After all, there's a reason it's called simple interest. And despite how much interest you earn on your principal, it's bound to be more interesting than your principal. Come on, Mrs. Lipschitz...look alive.

Mrs. Lipschitz?

Related or Semi-related Video

Finance: What is Interest Only Mortgage?17 Views

00:00

Finance allah shmoop what is an interest only mortgage Well

00:07

simply put it's when you only pay the rent on

00:10

the dough you borrowed you don't pay down the principal

00:14

you owe like if you have a three hundred thousand

00:16

dollars mortgage at six percent interest you're paying eighteen grand

00:19

a year to rent that money in six percent times

00:22

three hundred rands eighteen grand a year But the principal

00:25

you borrowed is likely due in thirty years So in

00:28

theory anyway if it were a normal mortgage you'd want

00:32

to pay down the principal little bit a month as

00:34

you go along like averaging ten grand a year in

00:37

principle pay down over thirty years That's times ten grand

00:41

right three hundred grand their total owning your home at

00:44

the end yeah yeah priceless that's what holmes work So

00:47

why would you want an interest only mortgage Well for

00:51

one thing the monthly payments or less so maybe you

00:54

could afford morehouse If on a thirty year three hundred

00:57

thousand dollar loan at six percent you're paying interest only

01:00

while you're writing a check each month for eighteen thousand

01:03

divided by twelve or fifteen hundred bucks maybe that's all

01:06

You can afford well the extra five hundred bucks arm

01:09

or you'd right toe pay down your principles Just not

01:12

something you can really do right now Maybe after three

01:15

years of scrimping and saving well you'll be able to

01:18

start paying down that principal reducing risk and making life

01:21

easier all the way around But right now you can't

01:24

afford it so the only thing you can do is

01:26

do the interest only dance Well the other reason you

01:28

might want an interest only mortgages that interest costs are

01:31

tax deductible Principal pay down costs are not so if

01:37

in a given mortgage payment of say eighteen hundred bucks

01:40

a month where three hundred of it is principal pay

01:43

down and fifteen hundred of it is interest well on

01:47

ly the fifteen hundred is tax deductible That three hundred

01:51

of pay down is not And if you're a forty

01:53

percent taxpayer the government is essentially picking up the tax

01:58

savings on the fifteen hundred times a forty percent at

02:02

six hundred dollars in interest You're paying such that they

02:05

quote feel unquote like the fifteen hundred is really only

02:10

about nine hundred a month in cost to you the

02:13

three hundred bucks and principal paydown feels like a full

02:16

three hundred dollars So some people seeking tio optimize their

02:19

tax deductions live in the world of interest only mortgages

02:23

and let the government for a change You know work 00:02:26.24 --> [endTime] for them How's that feel same all Take it

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