HELP

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HELP

by AJWILL » Fri Jul 13, 2012 6:41 am
the annual interest rate earned by an investment increased by 10% from last year to this year. if the annual interest rate earned by the investment this year was 10 percent, what was the annual interest rate last year?
A)1%
B)1.1%
C)9.1%
D)10%
E)10.8%

may be its a very easy question, but i cant form an equation! please help.
wht i did was-- r(1.1)=.1
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by eagleeye » Fri Jul 13, 2012 7:07 am
AJWILL wrote:the annual interest rate earned by an investment increased by 10% from last year to this year. if the annual interest rate earned by the investment this year was 10 percent, what was the annual interest rate last year?
A)1%
B)1.1%
C)9.1%
D)10%
E)10.8%

may be its a very easy question, but i cant form an equation! please help.
wht i did was-- r(1.1)=.1
r(1.1)=.1 is correct.
r = 0.1/1.1 = 0.091 = 9.1%
:)

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by Anurag@Gurome » Fri Jul 13, 2012 7:15 am
AJWILL wrote:the annual interest rate earned by an investment increased by 10% from last year to this year. if the annual interest rate earned by the investment this year was 10 percent, what was the annual interest rate last year?
Say, last years rate was r%.
Hence, this years rate = (r + 10% of r)% = 1.1r%

Hence, 1.1r = 10 --> r = 10/1.1 = 100/11 = 9.1...

The correct answer is C.
Anurag Mairal, Ph.D., MBA
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