Investment problems usually
involve simple annual interest (as opposed to 深圳超1.68万套房源被锁 或陷旧改市场危情), using
the interest formula I = Prt, where I stands
for the interest on the original investment, P stands for the amount of the original investment (called the "principal"), r is the interest rate (expressed in decimal form), and t is the time.

For annual interest,
the time t must be in years. If they give you a time of, say, nine months, you must
first convert this to ^{9}/_{12} = ^{3}/_{4} = 0.75 years. Otherwise, you'll get the wrong answer. The time units must
match the interest-rate units. If you got a loan from your friendly neighborhood
loan shark, where the interest rate is monthly, rather than yearly, then
your time must be measured in terms of months.

'People in the community are affected by what I write, ' he says. 以下是五个脱颖而出的、值得在2014年加以关注的初创企业。 Dachis says: 2011 saw a huge bounce for Dominos in brand enthusiasm from their brand relaunch which 2012 just couldn’t match. It’s a shame they can’t redesign their recipes every year. Mr Karl added: “We would have likely had a record [year] even without El , but it pushed it way over the top.” 9.微笑

In all cases of these problems,
you will want to substitute all known information into the "I
= Prt" equation,
and then solve for whatever is left.

You put $1000 into an investment yielding 6% annual interest; you left the money in for two years. How much interest
do you get at the end of those two years?

In this case, P = $1000, r = 0.06 (because I have to convert the percent to decimal form), and the time
is t = 2. Substituting,
I get:

住房委托中介出租 却被用于注册公司

I will get $120 in interest.

Advertisement

Another example would be:

You invested $500 and received $650 after three years. What had been the interest rate?

For this exercise, I
first need to find the amount of the interest. Since interest is added
to the principal, and since P = $500, then I = $650 – 500 = $150.
The time is t = 3. Substituting
all of these values into the simple-interest formula, I get:

You have $50,000 to invest,
and two funds that you'd like to invest in. The You-Risk-It Fund (Fund
Y) yields 14% interest. The Extra-Dull Fund (Fund X) yields 6% interest. Because of college financial-aid implications, you don't think
you can afford to earn more than $4,500 in interest income this year. How much should you put in each fund?"

The problem here comes
from the fact that I'm splitting that $50,000 in principal into two smaller amounts. Here's how to handle this:

I

P

r

t

Fund
X

?

?

0.06

1

Fund
Y

?

?

0.14

1

total

4,500

50,000

---

---

How do I fill in for
those question marks? I'll start with the principal P.
Let's say that I put "x"
dollars into Fund X, and "y"
dollars into Fund Y. Then x + y = 50,000.
This doesn't help much, since I only know how to solve equations in
one variable. But then I notice that I can solve x + y = 50,000 to get y = $50,000 – x.

THIS TECHNIQUE IS
IMPORTANT! The
amount in Fund Y is (the total) less (what we've already accounted for
in Fund X), or 50,000
– x. You will need this technique, this "how much is left" construction,
in the future, so make sure you understand it now.

I

P

r

t

Fund
X

?

x

0.06

1

Fund
Y

?

50,000
– x

0.14

1

total

4,500

50,000

---

---

为回应这起事件，借贷宝12月1日在其新浪微博上发表了一份公告，强调用裸照作抵押贷款是用户之间的私人交易，该公司无法加以管理。 二年级的佩恩，作为一个乐透秀，因为脚伤很多时间不能上场，并且没有表现出作为投手或者防守球员的一点点进步。 The pipelines were building in spite of poor performance for this year’s high-profile deal from Snap, the owner of Snapchat, in the US and investor concerns that a strengthening euro may curtail the earnings recovery in Europe.

I

P

r

t

Fund
X

0.06x

x

0.06

1

Fund
Y

0.14(50,000
– x)

50,000
– x

0.14

1

total

4,500

50,000

---

---

Since the interest from
Fund X and the interest from Fund Y will add up to $4,500, I can add
down the "interest" column, and set this sum equal to the
given total interest:

I should put $31,250 into Fund X, and $18,750 into Fund Y.

Note that the answer did
not involve "neat" values like "$10,000"
or "$35,000".
You should understand that this means that you cannot always expect to
be able to use "guess-n-check" to find your answers. You really
do need to know how to do these exercises.