February 18, 2019 February 18, 2019 10:00 PM PST 11:00 PM PST We don’t care what your relationship status this year  we love you just the way you are. AND we want you to crush the GMAT! February 18, 2019 February 18, 2019 10:00 PM PST 11:00 PM PST Buy "AllInOne Standard ($149)", get free Daily quiz (2 mon). Coupon code : SPECIAL
Author 
Message 
TAGS:

Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 52938

On a certain date, Hannah invested $5,000 at x percent
[#permalink]
Show Tags
20 Aug 2012, 02:25
Question Stats:
77% (01:28) correct 23% (01:14) wrong based on 1686 sessions
HideShow timer Statistics




Math Expert
Joined: 02 Sep 2009
Posts: 52938

Re: On a certain date, Hannah invested $5,000 at x percent
[#permalink]
Show Tags
20 Aug 2012, 02:25
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.
_________________
New to the Math Forum? Please read this: Ultimate GMAT Quantitative Megathread  All You Need for Quant  PLEASE READ AND FOLLOW: 12 Rules for Posting!!! Resources: GMAT Math Book  Triangles  Polygons  Coordinate Geometry  Factorials  Circles  Number Theory  Remainders; 8. Overlapping Sets  PDF of Math Book; 10. Remainders  GMAT Prep Software Analysis  SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS)  Tricky questions from previous years.
Collection of Questions: PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.
What are GMAT Club Tests? Extrahard Quant Tests with Brilliant Analytics




Intern
Joined: 19 Apr 2012
Posts: 23

Re: On a certain date, Hannah invested $5,000 at x percent
[#permalink]
Show Tags
20 Aug 2012, 09:17
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.



Intern
Joined: 05 Mar 2012
Posts: 49

Re: On a certain date, Hannah invested $5,000 at x percent
[#permalink]
Show Tags
22 Aug 2012, 13:05
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.



Intern
Joined: 19 Apr 2012
Posts: 23

Re: On a certain date, Hannah invested $5,000 at x percent
[#permalink]
Show Tags
22 Aug 2012, 13:19
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.



Intern
Joined: 05 Mar 2012
Posts: 49

Re: On a certain date, Hannah invested $5,000 at x percent
[#permalink]
Show Tags
22 Aug 2012, 13:24
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.



Intern
Joined: 19 Apr 2012
Posts: 23

Re: On a certain date, Hannah invested $5,000 at x percent
[#permalink]
Show Tags
22 Aug 2012, 13:47
Ah, sorry, my mistake. But that doesen't change so much. It is still unsufficient.



Intern
Joined: 05 Mar 2012
Posts: 49

Re: On a certain date, Hannah invested $5,000 at x percent
[#permalink]
Show Tags
22 Aug 2012, 13:52
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.



Math Expert
Joined: 02 Sep 2009
Posts: 52938

Re: On a certain date, Hannah invested $5,000 at x percent
[#permalink]
Show Tags
24 Aug 2012, 06:25
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.
_________________
New to the Math Forum? Please read this: Ultimate GMAT Quantitative Megathread  All You Need for Quant  PLEASE READ AND FOLLOW: 12 Rules for Posting!!! Resources: GMAT Math Book  Triangles  Polygons  Coordinate Geometry  Factorials  Circles  Number Theory  Remainders; 8. Overlapping Sets  PDF of Math Book; 10. Remainders  GMAT Prep Software Analysis  SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS)  Tricky questions from previous years.
Collection of Questions: PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.
What are GMAT Club Tests? Extrahard Quant Tests with Brilliant Analytics



Intern
Joined: 13 Nov 2015
Posts: 9

Re: On a certain date, Hannah invested $5,000 at x percent
[#permalink]
Show Tags
19 Dec 2015, 14:50
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!



Target Test Prep Representative
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 4920
Location: United States (CA)

Re: On a certain date, Hannah invested $5,000 at x percent
[#permalink]
Show Tags
19 May 2016, 06:42
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.
_________________
Scott WoodburyStewart
Founder and CEO
GMAT Quant SelfStudy Course
500+ lessons 3000+ practice problems 800+ HD solutions



Intern
Status: Don't watch the clock,Do what it does, Keep Going.
Joined: 10 Jan 2017
Posts: 37

Re: On a certain date, Hannah invested $5,000 at x percent
[#permalink]
Show Tags
18 Sep 2017, 02:47
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



NonHuman User
Joined: 09 Sep 2013
Posts: 9843

Re: On a certain date, Hannah invested $5,000 at x percent
[#permalink]
Show Tags
05 Oct 2018, 15:43
Hello from the GMAT Club BumpBot! Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up  doing my job. I think you may find it valuable (esp those replies with Kudos). Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
GMAT Books  GMAT Club Tests  Best Prices on GMAT Courses  GMAT Mobile App  Math Resources  Verbal Resources




Re: On a certain date, Hannah invested $5,000 at x percent
[#permalink]
05 Oct 2018, 15:43






