The annual interest rate earned by an investment increased by 10 perce

Question

The annual interest rate earned by an investment increased by 10 percent from last year to this year. If the annual interest rate earned by the investment this year was 11 percent, what was the annual interest rate last year?

A) 1%
B) 1.1%
C) 9.1%
D) 10%
E) 10.8%

A) 1% 
B) 1.1% 
C) 9.1% 
D) 10% 
E) 10.8%

diegocml · Accepted Answer

I had to read the question stem 4 times to make sense of what the question was asking. Very confusing, but here it goes my approach.

Say you're not able to quickly set up your work as our friends did above, just do a word by word translation.

Call ' x ' the interest rate last year

Some value x increased by 10% last year and the result is a rate of 11%.

\cfrac { 110 }{ 100 } (x)=11\ x=\cfrac { 11\ast 100 }{ 110 } \ x=10

sashiim20 · Answer

The annual interest rate earned by an investment increased by 10 percent from last year to this year. If the annual interest rate earned by the investment this year was 11 percent, what was the annual interest rate last year?

A) 1%
B) 1.1%
C) 9.1%
D) 10%
E) 10.8%

Let annual interest rate last year be = x%
Annual interest rate increased by 10% from last year to this year = 110% of x = 1.1x%
Interest rate this year = 11% = 1.1x %
\(\frac{1.1x}{100}\) = \(\frac{11}{100}\)
x = \(\frac{11}{1.1}\) = 10%
Answer D...

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hsbinfy · Answer

should be 10

increased it by 10 % will be =10+1=11

Badari · Answer

Let us suppose the interest rate last year is X, This year the interest rate is increased by 10%. Hence this year interest rate would be 1.1*X.
Setting up the equation -----> 11=1.1*x
X=10%

Option D

ScottTargetTestPrep · Answer

We can create the following equation in which x = the interest rate last year:

1.1x = 0.11

x = 0.11/1.1 = 11/110 = 1/10 = 0.1 = 10%

Answer: D

ziyadttp · Answer

So here is my solution:

Let x be the original interest rate and A be the amount.
Given x increased by 10 percent from last year to this year
So current interest rate is x+0.1x
The annual intrest rate this year was 11 percent of the amount, So 
x+0.1x = 0.11A
1.1x=0.11A
x= 1/10 of A
Since the answer is in percentage x% = 10% of A

Can someone please show me a simpler method to do this? The question is rated at 5 percent difficulty so I'm hoping there is a simpler way.

Thanks

2020prep2020 · Answer

How would have the wording of the question look like if the interest rate had increased from 1% to 11%?

MHIKER · Answer

The original interest rate of Last year was = x
Total after increase = 1.10x

Interest earned this year 11% = 0.11

So, 1.10x = 0.11
x = 10%

Answer D.

MHIKER · Answer

Let, Before increase interest rate was 100; After increasing 10% the interest rate was 110

Now, New is rate 110, Old rate was 100
If new rate is 11 the Old rate was:

\frac{100}{110} * 100

=10%

The Answer is D.

Abhishek009 · Answer

Clean (D) 110% of 10 = 11, Hence Answer must be (D)

ueh55406 · Answer

Thank God for this forum, my brain was hurting reading this question. At one point I was reading it aloud, hoping it would make some sense.

Sa800 · Answer

Why dont you have a divided by 100 under the 11
so 11/100 (since a percent means out of a 100)

Posted from my mobile device

bumpbot · Answer

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The annual interest rate earned by an investment increased by 10 perce

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