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On a certain date, Hannah invested $5,000 at x percent [#permalink]
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20 Aug 2012, 03:25
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Re: On a certain date, Hannah invested $5,000 at x percent [#permalink]
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20 Aug 2012, 03:25
SOLUTIONOn a certain date, Hannah invested $5,000 at x percent simple annual interest and a different amount at y percent simple annual interest. What amount did Hannah invest at y percent simple annual interest?Say the amount Hannah invested at y percent is I. (1) The total amount of interest earned by Hannah's two investments in one year was $900. Given: \(5,000*\frac{x}{100}+I*\frac{y}{100}=900\). We have one equation and three unknowns, hence we cannot solve for I. Not sufficient. (2) Hannah invested the $5,000 at 6 percent simple annual interest. Given: \(x=6%\). Not sufficient. (1)+(2) We have that \(5,000*\frac{6}{100}+I*\frac{y}{100}=900\). We still have one equation and two unknowns, hence we cannot solve for I. Not sufficient. Answer: E.
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Re: On a certain date, Hannah invested $5,000 at x percent [#permalink]
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20 Aug 2012, 10:17
The answer is (E).
The Formula to calculate the interest is the following:
\(\frac{x}{100}*X + \frac{y}{100}*Y = Interest\)
\(X + Y = 5000\) "The total amount of interest earned by Hannah's two investments in one year was $900."
\(\frac{x}{100}*(5000Y) + \frac{y}{100}*Y = 900\)
No Information about y or x hence unsufficient.
"(2) Hannah invested the $5,000 at 6 percent simple annual interest."
We have the information about x + y = 6%, but we don't know what is exactly y or x, so unsufficient.



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Re: On a certain date, Hannah invested $5,000 at x percent [#permalink]
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22 Aug 2012, 14:05
Alexmsi wrote: The answer is (E).
The Formula to calculate the interest is the following:
\(\frac{x}{100}*X + \frac{y}{100}*Y = Interest\)
\(X + Y = 5000\) "The total amount of interest earned by Hannah's two investments in one year was $900."
\(\frac{x}{100}*(5000Y) + \frac{y}{100}*Y = 900\)
No Information about y or x hence unsufficient.
"(2) Hannah invested the $5,000 at 6 percent simple annual interest."
We have the information about x + y = 6%, but we don't know what is exactly y or x, so unsufficient. Although I agree that the answer is E, I'm not sure how you came up with X + Y = 5000. Hannah had two principles, one valued at 5,000 undergoing x interest and some unknown principle undergoing y interest.



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Re: On a certain date, Hannah invested $5,000 at x percent [#permalink]
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22 Aug 2012, 14:19
Hello, "On a certain date, Hannah invested $5,000 at x percent simple annual interest and a different amount at y percent simple annual interest." So, she invested some money at x percent and another part at y percent. The two parts together are X and Y. X+Y = 5000.



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Re: On a certain date, Hannah invested $5,000 at x percent [#permalink]
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22 Aug 2012, 14:24
Alexmsi wrote: Hello, "On a certain date, Hannah invested $5,000 at x percent simple annual interest and a different amount at y percent simple annual interest." So, she invested some money at x percent and another part at y percent. The two parts together are X and Y. X+Y = 5000. But that's my beef, the question never says that the total amount invested equals 5,000.



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Re: On a certain date, Hannah invested $5,000 at x percent [#permalink]
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22 Aug 2012, 14:47
Ah, sorry, my mistake. But that doesen't change so much. It is still unsufficient.



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Re: On a certain date, Hannah invested $5,000 at x percent [#permalink]
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22 Aug 2012, 14:52
Alexmsi wrote: Ah, sorry, my mistake. But that doesen't change so much. It is still unsufficient. Just checking, I agree as well. Interest problems always throw me off so I wanted to make sure I am still good.



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Re: On a certain date, Hannah invested $5,000 at x percent [#permalink]
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24 Aug 2012, 07:25
SOLUTIONOn a certain date, Hannah invested $5,000 at x percent simple annual interest and a different amount at y percent simple annual interest. What amount did Hannah invest at y percent simple annual interest?Say the amount Hannah invested at y percent is I. (1) The total amount of interest earned by Hannah's two investments in one year was $900. Given: \(5,000*\frac{x}{100}+I*\frac{y}{100}=900\). We have one equation and three unknowns, hence we cannot solve for I. Not sufficient. (2) Hannah invested the $5,000 at 6 percent simple annual interest. Given: \(x=6%\). Not sufficient. (1)+(2) We have that \(5,000*\frac{6}{100}+I*\frac{y}{100}=900\). We still have one equation and two unknowns, hence we cannot solve for I. Not sufficient. Answer: E.
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Re: On a certain date, Hannah invested $5,000 at x percent [#permalink]
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19 Dec 2015, 15:50
Can someone tell me why can't I treat x and y as known? I was thinking that the answer should be (A), since from (A), we can represent the amount of money Hannah invested in y percent simple annual interest rate as "[900  5000*(x/100)]/[y/100]."
I don't think the question makes it clear that we should treat x and y as unknowns.
Thanks!



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Re: On a certain date, Hannah invested $5,000 at x percent [#permalink]
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19 May 2016, 07:42
Bunuel wrote: On a certain date, Hannah invested $5,000 at x percent simple annual interest and a different amount at y percent simple annual interest. What amount did Hannah invest at y percent simple annual interest?
(1) The total amount of interest earned by Hannah's two investments in one year was $900. (2) Hannah invested the $5,000 at 6 percent simple annual interest. Solution: We are given that Hannah invested $5,000 at x percent simple annual interest and invested another amount at y percent simple annual interest. We need to determine the amount that she invested at y percent simple annual interest. We can let this amount be n. Statement One Alone:The total amount of interest earned by Hannah’s two investments in one year was $900. Using statement one, we can set up the following equation: 5,000(x/100) + n(y/100) = 900 Multiplying the entire equation by 100 we have: 5,000x + ny = 90,000 Since we do not know the value of x or y, we cannot determine the value of n, and thus statement one alone is not sufficient to answer the question. We can eliminate answer choices A and D. Statement Two Alone:Hannah invested the $5,000 at 6 percent simple annual interest. From statement two we know that x is 6 and thus we can determine how much interest Hannah made from her investment at x percent interest. 5,000 x 6/100 = $300 However, we still do not know how much money was invested at y percent simple annual interest. Statement two alone is not sufficient to answer the question. We can eliminate answer choice B. Statements One and Two Together:From both statements we have the following equation: 300 + ny = 900 Since we do not know the value of y, we still cannot determine a value for n. The answer is E.
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Re: On a certain date, Hannah invested $5,000 at x percent [#permalink]
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18 Sep 2017, 03:47
1. I1+ I2=900 not sufficient 2. I1=(5000*6*1)/100=300 so I2=600 but there are two unknowns for I2 R=y% an the principle Not sufficient
E




Re: On a certain date, Hannah invested $5,000 at x percent
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