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At the beginning of January 2003, Elizabeth invested money in an accou [#permalink]
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10 Mar 2015, 06:03
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Re: At the beginning of January 2003, Elizabeth invested money in an accou [#permalink]
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10 Mar 2015, 06:29
Hi The answer is E as we don't know the time period of the compounding whether 3 months or 6 month and so
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Re: At the beginning of January 2003, Elizabeth invested money in an accou [#permalink]
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10 Mar 2015, 12:56
ANSWER IS E....
in the compounding interests rates problems we need to know all initial amount of money , time period , and the rate of interest to calculate the final amount of money
but here in the 2 data we don't know the TIME PERIOD in which the rate of interest compounds , for example , we don't know the rate compounding semi annually or quaterlly , etc..
so answer is E...



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Re: At the beginning of January 2003, Elizabeth invested money in an accou [#permalink]
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10 Mar 2015, 13:16
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my choice  E statement 1 tells us her initial investment, nevertheless we do not know anything about the interest rate and the compounding period. statement 2 tells us what was the interest rate, however we again do not have all information that is needed.
statement 1+2: we know the initial amount, we know the APR, but we do not know the compounding period. the amount earned on 7% interest, compounded semiannually is different than the amount earned on 7% interest, compounded quarterly or monthly.
hence the only answer left is E.



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Re: At the beginning of January 2003, Elizabeth invested money in an accou [#permalink]
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10 Mar 2015, 19:21
Bunuel wrote: At the beginning of January 2003, Elizabeth invested money in an account that collected interest, compounding more frequently than a year. Assume the annual percentage rate of interest remained constant. What is the total amount she has invested after seven years?
(1) her initial investment was $20,000 (2) the account accrued 7% annual interest
Kudos for a correct solution. Statement 1: Dont know the compounding frequency or interest rate Insufficient Statement 2: Dont know the principal or compounding frequency Insufficient Combined, we still dont know the compounding frequency Answer: E



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Re: At the beginning of January 2003, Elizabeth invested money in an accou [#permalink]
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10 Mar 2015, 19:35
Compound interest = P *(1+ r/n)^nt; P=initial money invested, r=rate of interest, n= #of times/year interest is compounded, t = time. 1. P is given , no information about r & n; therefore Not Sufficient 2. r is given , no information about P & n; therefore Not Sufficient C: 1+2 P & r are given no information about n; therefore not sufficient. Therefore answer is E
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Re: At the beginning of January 2003, Elizabeth invested money in an accou [#permalink]
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11 Mar 2015, 07:34
the answer is E we do not know the compounding period where all we know is that it is less than a year
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Re: At the beginning of January 2003, Elizabeth invested money in an accou [#permalink]
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11 Mar 2015, 07:42
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+1 for E. Since the frequency of the time period is not given. Its not possible to find the end amount even if with the information given in the statements, separate or combined.
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Re: At the beginning of January 2003, Elizabeth invested money in an accou [#permalink]
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15 Mar 2015, 22:42
Bunuel wrote: At the beginning of January 2003, Elizabeth invested money in an account that collected interest, compounding more frequently than a year. Assume the annual percentage rate of interest remained constant. What is the total amount she has invested after seven years?
(1) her initial investment was $20,000 (2) the account accrued 7% annual interest
Kudos for a correct solution. MAGOOSH OFFICIAL SOLUTION:In order to determine the total amount at the end of an investment, we would need to know three things: (a) the initial deposit; (b) the annual percentage rate; and (c) the compounding period. Statement #1 tells us the initial deposit but not the annual percentage rate. Insufficient. Statement #2 tells us the annual percentage rate but not the initial deposit. Insufficient. Together, we know both the initial deposit and the annual percentage rate, but we still don’t know the compounding period. All we know is that it’s less than a year, but quarterly compounding vs. monthly compounding vs. daily compounding would produce different total amounts at the end. Without knowing the exact compounding period, we cannot calculate a precise answer. Even together, the statements are insufficient. Answer = (E)
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Re: At the beginning of January 2003, Elizabeth invested money in an accou [#permalink]
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15 Mar 2015, 22:42
Bunuel wrote: Bunuel wrote: At the beginning of January 2003, Elizabeth invested money in an account that collected interest, compounding more frequently than a year. Assume the annual percentage rate of interest remained constant. What is the total amount she has invested after seven years?
(1) her initial investment was $20,000 (2) the account accrued 7% annual interest
Kudos for a correct solution. MAGOOSH OFFICIAL SOLUTION:In order to determine the total amount at the end of an investment, we would need to know three things: (a) the initial deposit; (b) the annual percentage rate; and (c) the compounding period. Statement #1 tells us the initial deposit but not the annual percentage rate. Insufficient. Statement #2 tells us the annual percentage rate but not the initial deposit. Insufficient. Together, we know both the initial deposit and the annual percentage rate, but we still don’t know the compounding period. All we know is that it’s less than a year, but quarterly compounding vs. monthly compounding vs. daily compounding would produce different total amounts at the end. Without knowing the exact compounding period, we cannot calculate a precise answer. Even together, the statements are insufficient. Answer = (E) Check other Compound Interest Problems in our Special Questions Directory.
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Re: At the beginning of January 2003, Elizabeth invested money in an accou [#permalink]
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29 Mar 2015, 06:06
Statement 01: It only tells us about the initial investment but information about rate of interest or how the rate was compounded. Statement 02: Only tells us the rate of interest annually, no information about initial principal. Combining A and B we get the initial principal and the rate of interest but no info about how the rate was calculated. Maybe a 3 month period or a 4 month period or half yearly . So E



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Re: At the beginning of January 2003, Elizabeth invested money in an accou [#permalink]
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30 Mar 2015, 03:43
E for me too. To calculate 'Value' in this Qn, we need to know : 1 rate compounded Quarterly or semi annually or monthly or what? 2 Principle invested 3 rate invested at Stat1: Gives 2, but no info on 1 and 3. NS Stat2: Gives 3, but no info about 1 or 2. NS Together : we dont have info about 1. Thus NS. E.
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Re: At the beginning of January 2003, Elizabeth invested money in an accou [#permalink]
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23 Jan 2017, 19:37
Bunuel wrote: At the beginning of January 2003, Elizabeth invested money in an account that collected interest, compounding more frequently than a year. Assume the annual percentage rate of interest remained constant. What is the total amount she has invested after seven years?
(1) her initial investment was $20,000 (2) the account accrued 7% annual interest
Kudos for a correct solution. I got this correct, but for another reason. Yes you have to know how often the money invested compounds, but I have an issue with the question wording. When you say, " What is the total amount she has invested after seven years", you are simply asking "How much money has she deposited in the account over the course of the seven years?" You know she deposited $20,000 initially, but did she ever deposit more than that? You need to know yes or no, and if yes, what the deposit amounts were and at what time the money was deposited into the account so that you could compute the end balance of the account after 7 years. If the question had been, "What is the total amount of money that had vested after seven years", then the question would be valid because it would simply be asking "How much total money would be in the account after 7 years?" Ie, "What is the balance after 7 years?" Does anyone else agree that there is an issue with the wording?



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Re: At the beginning of January 2003, Elizabeth invested money in an accou [#permalink]
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18 Mar 2018, 18:16
I just provides principle. No good. II just provides rate. No good. I+II provides what you need to calculate the amount if not for the part where it says "compounds more frequently than a year". r becomes r/frequency (unknown).
Answer E




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