GMAT Question of the Day: Daily via email | Daily via Instagram New to GMAT Club? Watch this Video

 It is currently 24 Feb 2020, 19:22

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

### Show Tags

22 Jun 2018, 00:55
1
26
00:00

Difficulty:

25% (medium)

Question Stats:

73% (01:23) correct 27% (01:24) wrong based on 1217 sessions

### HideShow timer Statistics

Robin invested a total of $12,000 in two investments, X and Y, so that the investments earned the same amount of simple annual interest. How many dollars did Robin invest in investment Y ? (1) Investment X paid 3 percent simple annual interest, and investment Y paid 6 percent simple annual interest. (2) Robin invested more than$1,000 in investment X.

NEW question from GMAT® Official Guide 2019

(DS02441)

_________________
Math Expert
Joined: 02 Aug 2009
Posts: 8254
Re: Robin invested a total of $12,000 in two investments, X and Y, so that [#permalink] ### Show Tags 22 Jun 2018, 02:25 4 2 Bunuel wrote: Robin invested a total of$12,000 in two investments, X and Y, so that the investments earned the same amount of simple annual interest. How many dollars did Robin invest in investment Y ?

(1) Investment X paid 3 percent simple annual interest, and investment Y paid 6 percent simple annual interest.
(2) Robin invested more than $1,000 in investment X. NEW question from GMAT® Official Guide 2019 (DS02441) Simple interest = PRT/100, where P is principal, R rate of interest and T is time.. Here time is 1 year, as we are looking at simple annual interest.. SAI=PR/100.. 1) statement I gives the two rate of interest as 3 and 6.. So z*3/100=(12000-z)*6/100.. It's a linear equation in z, you can find the value of z Sufficient 2) statement II tells us that Robin invested$1000 more..
Nothing much
Insufficient

A
_________________
Manager
Joined: 10 Jun 2018
Posts: 51
Location: Australia
Concentration: Technology, General Management
Schools: Other Schools
GPA: 2.88
WE: Science (Pharmaceuticals and Biotech)

### Show Tags

23 Jun 2018, 06:35
3
Top Contributor
Bunuel wrote:
Robin invested a total of $12,000 in two investments, X and Y, so that the investments earned the same amount of simple annual interest. How many dollars did Robin invest in investment Y ? (1) Investment X paid 3 percent simple annual interest, and investment Y paid 6 percent simple annual interest. (2) Robin invested more than$1,000 in investment X.

Let X = The number of dollars invested in investment X
Let Y = The number of dollars invested in investment Y

Target question: What is the value of Y?

Given: Robin invested a total of $12,000 in two investments, X and Y, so that the investments earned the same amount of simple annual interest. If the total investment is$12,000, we can write: X + Y = 12,000

Statement 1: Investment X paid 3 percent simple annual interest, and investment Y paid 6 percent simple annual interest.
So, the annual interest paid by investment X = 0.03X and the interest paid by investment Y = 0.06Y
Since the annual interest on the two investments are EQUAL, we can write: 0.03X = 0.06Y
We now have the following system of linear equations:
X + Y = 12,000
0.03X = 0.06Y
Since we COULD solve this system for Y, we COULD answer the target question with certainty (but we would never waste valuable time actually solving the system!)
Since we could answer the target question with certainty, statement 1 is SUFFICIENT

Statement 2: Robin invested more than $1,000 in investment X. Since we don't know the exact value of the amount Robin invested in X, and since we don't know anything about the interest rates for the investments, we cannot answer the target question with certainty. So, statement 2 is NOT SUFFICIENT ASIDE: If you're not convinced that statement 2 is not sufficient, consider these two cases: Case a: X = 6,000, Y = 6,000, and the interest rate for each investment is 10%. Notice that the interest for each investment will be equal. Here, the answer to the target question is Y = 6,000 Case b: X = 2000, Y = 10,000, the interest rate for investment X is 50%, and the interest rate for investment Y is 10%. Notice that the interest for each investment will be equal. Here, the answer to the target question is Y = 10,000 Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT Answer: A Cheers, Brent _________________ Test confidently with gmatprepnow.com Intern Joined: 10 Feb 2018 Posts: 2 Re: Robin invested a total of$12,000 in two investments, X and Y, so that  [#permalink]

### Show Tags

01 Jan 2019, 03:56
2
How are we able to infer that thetime period of investments are same ?
e-GMAT Representative
Joined: 04 Jan 2015
Posts: 3256
Re: Robin invested a total of $12,000 in two investments, X and Y, so that [#permalink] ### Show Tags 22 Jun 2018, 02:47 1 1 Solution Given: • Robin invested total$12000 in two investments, X and Y
• The investments earned same amount of simple annual interest

To find:
• The amount (dollars) Robin invested in Y

Analysing Statement 1
• As per the information given in statement 1, investment X paid 3% simple interest whereas investment Y paid 6% simple interest
• If we assume that investment in X is P, then investment in Y will be (12000 – P)
• As the simple annual interest earned is same, we can write:
o $$\frac{P * 3}{100} = \frac{(12000 – P) * 6}{100}$$
• We can get the value of P as well as (12000 – P)

Hence, statement 1 is sufficient to answer

Analysing Statement 2
• As per the information given in statement 2, Robin invested more than $1000 in investment X o From this, we cannot find out the exact investment in X and Y individually Hence, statement 2 is not sufficient to answer Hence, the correct answer is option A. Answer: A _________________ Manager Joined: 06 May 2015 Posts: 62 Location: India Schools: Darden '21 GPA: 4 Re: Robin invested a total of$12,000 in two investments, X and Y, so that  [#permalink]

### Show Tags

16 Sep 2018, 09:33
Bunuel wrote:
Robin invested a total of $12,000 in two investments, X and Y, so that the investments earned the same amount of simple annual interest. How many dollars did Robin invest in investment Y ? (1) Investment X paid 3 percent simple annual interest, and investment Y paid 6 percent simple annual interest. (2) Robin invested more than$1,000 in investment X.

NEW question from GMAT® Official Guide 2019

(DS02441)

(a)
X+Y = 12000
0.03X = 0.06Y
X = 2Y
Hence solvable, Suffficient

(b)
X>1000 -> Not sufficient
Intern
Joined: 28 Mar 2019
Posts: 7

### Show Tags

26 Jul 2019, 11:05
Azedenkae wrote:
Statement 1: If investment Y paid double the interest of investment X, then investment X must be double that of investment Y to get the same amount of interest earnt.

Therefore, the ratio of X:Y is 2:1, and so investment X is $8000, investment Y is$4000.

Statement 2 ain’t got enough info. :P

Posted from my mobile device

Yup I followed the same approach. Since 3 and 6 percent have to result in same interest the principals are probably in 2:1 leading to 8000 and 4000 and you can find out.
B doesn't help on it's own and does nothing to support A either.
Hence A
_________________
The Moment You Think About Giving Up, Think Of The Reason Why You Held On So Long

Learn from the Legend himself: All GMAT Ninja LIVE YouTube videos by topic
You are missing on great learning if you don't know what this is: Project SC Butler
Manager
Joined: 12 Mar 2017
Posts: 205
Location: India
Concentration: Strategy, General Management
GMAT 1: 700 Q49 V37
GPA: 4
Re: Robin invested a total of $12,000 in two investments, X and Y, so that [#permalink] ### Show Tags 02 Sep 2019, 10:37 chetan2u wrote: Bunuel wrote: Robin invested a total of$12,000 in two investments, X and Y, so that the investments earned the same amount of simple annual interest. How many dollars did Robin invest in investment Y ?

(1) Investment X paid 3 percent simple annual interest, and investment Y paid 6 percent simple annual interest.
(2) Robin invested more than $1,000 in investment X. NEW question from GMAT® Official Guide 2019 (DS02441) Simple interest = PRT/100, where P is principal, R rate of interest and T is time.. Here time is 1 year, as we are looking at simple annual interest.. SAI=PR/100.. 1) statement I gives the two rate of interest as 3 and 6.. So z*3/100=(12000-z)*6/100.. It's a linear equation in z, you can find the value of z Sufficient 2) statement II tells us that Robin invested$1000 more..
Nothing much
Insufficient

A

chetan2u

How can we infer that the time for both investments was the same. It could’ve been different. In that case E would be the answer
Intern
Joined: 12 Dec 2012
Posts: 15
Location: United States (GA)
GMAT 1: 680 Q46 V37
GPA: 4
Re: Robin invested a total of $12,000 in two investments, X and Y, so that [#permalink] ### Show Tags 20 Sep 2019, 05:01 For many folks(including me), who are wondering where is the time period specified, focus on the language of the question. That is the trick in this otherwise simple question. "Robin invested a total of$12,000 in two investments, X and Y, so that the investments earned the same amount of simple annual interest. How many dollars did Robin invest in investment Y ?"

"simple annual interest" and not "simple interest" so, the time period is 1 year.
Intern
Joined: 27 May 2018
Posts: 17
Re: Robin invested a total of $12,000 in two investments, X and Y, so that [#permalink] ### Show Tags 25 Dec 2019, 22:23 Bunuel wrote: Robin invested a total of$12,000 in two investments, X and Y, so that the investments earned the same amount of simple annual interest. How many dollars did Robin invest in investment Y ?

(1) Investment X paid 3 percent simple annual interest, and investment Y paid 6 percent simple annual interest.
(2) Robin invested more than $1,000 in investment X. NEW question from GMAT® Official Guide 2019 (DS02441) Ans -A Simple weighted Average problem. Interest ratio 3:6 i.e. 1:2 For interest earned to be same, X: Y must be opposite of Interest ratio i.e. 2:1.( 8000:4000) 8000x3=4000x6 _________________ GMAT Side effects ------------------- G-Groggy M-Mental A-Annoyed T-Twitted Re: Robin invested a total of$12,000 in two investments, X and Y, so that   [#permalink] 25 Dec 2019, 22:23
Display posts from previous: Sort by