Last visit was: 25 Apr 2024, 10:15 It is currently 25 Apr 2024, 10:15

Close
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
Your Progress

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
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Close
Request Expert Reply
Confirm Cancel
SORT BY:
Date
User avatar
Intern
Intern
Joined: 14 May 2008
Posts: 19
Own Kudos [?]: 771 [20]
Given Kudos: 0
Send PM
Most Helpful Reply
Math Expert
Joined: 02 Sep 2009
Posts: 92914
Own Kudos [?]: 618967 [5]
Given Kudos: 81595
Send PM
General Discussion
User avatar
Senior Manager
Senior Manager
Joined: 23 Sep 2007
Posts: 398
Own Kudos [?]: 1510 [1]
Given Kudos: 0
Send PM
User avatar
SVP
SVP
Joined: 11 Mar 2008
Posts: 1579
Own Kudos [?]: 291 [1]
Given Kudos: 0
Location: Southern California
Concentration: Investment Banking
Schools:Chicago (dinged), Tuck (November), Columbia (RD)
Send PM
Re: $10,000 is deposited in a certain account that pays r percent annual [#permalink]
1
Kudos
quantum wrote:
10. $10,000 is deposited in a certain account that pays r percent annual interest compounded annually, the amount D(t), in dollars, that the deposit will grow to in t years in given by D(t)=10,000(1+(r/100))t What amount will the deposit grow to in 3 years?

(1) D(t) = 11,000
(2) r=10

Can anybody explain the logic please?
Thank you!


This is D indeed.

Rephrased, knowing that t=3, the equation is: D(t)=10,000(1+(r/100))3 - If you know either D(t) or r, you can solve this equation for all variables.
User avatar
Manager
Manager
Joined: 25 Nov 2011
Posts: 126
Own Kudos [?]: 870 [0]
Given Kudos: 20
Location: India
Concentration: Technology, General Management
GPA: 3.95
WE:Information Technology (Computer Software)
Send PM
Re: $10,000 is deposited in a certain account that pays r percent annual [#permalink]
gmatnub wrote:
B

statement 1: D(t) = 11000, but t could be any thing, it could be 10 years or 2 years.
insuff

statement 2: suff, because it gives the interest rate and you have the years in the stem, you can find out the total after 3 years.


D(t) means a function. Now, constant values (i.e., 11000) can't be equated with functions because as far as I can think, no one can come up with an equation with a variable that always produces the same value for all values of the variable. Hence, in this question, we must assume that D(t) gives 11000 for some value of t. With that thinking, D should be the correct answer.
User avatar
Manager
Manager
Joined: 17 Nov 2011
Status:Employed
Posts: 67
Own Kudos [?]: 433 [0]
Given Kudos: 10
Location: Pakistan
Concentration: International Business, Marketing
GMAT 1: 720 Q49 V40
GPA: 3.2
WE:Business Development (Internet and New Media)
Send PM
Re: $10,000 is deposited in a certain account that pays r percent annual [#permalink]
Chembeti wrote:
gmatnub wrote:
B

statement 1: D(t) = 11000, but t could be any thing, it could be 10 years or 2 years.
insuff

statement 2: suff, because it gives the interest rate and you have the years in the stem, you can find out the total after 3 years.


D(t) means a function. Now, constant values (i.e., 11000) can't be equated with functions because as far as I can think, no one can come up with an equation with a variable that always produces the same value for all values of the variable. Hence, in this question, we must assume that D(t) gives 11000 for some value of t. With that thinking, D should be the correct answer.


Guys \(t\) is already give, No? \(3\) years. So \(t\) should be \(3\), No? Hence D
Manager
Manager
Joined: 06 Jan 2012
Status:May The Force Be With Me (D-DAY 15 May 2012)
Posts: 165
Own Kudos [?]: 2095 [0]
Given Kudos: 33
Location: India
Concentration: General Management, Entrepreneurship
Send PM
Re: $10,000 is deposited in a certain account that pays r percent annual [#permalink]
quantum wrote:
$10,000 is deposited in a certain account that pays r percent annual interest compounded annually, the amount D(t), in dollars, that the deposit will grow to in t years in given by D(t)=10,000(1+(r/100))^t. What amount will the deposit grow to in 3 years?

(1) D(1) = 11,000
(2) r=10


Below is a flawed version of the above correct question:
10. $10,000 is deposited in a certain account that pays r percent annual interest compounded annually, the amount D(t), in dollars, that the deposit will grow to in t years in given by D(t)=10,000(1+(r/100))t What amount will the deposit grow to in 3 years?

(1) D(t) = 11,000
(2) r=10

Bunuel


Hi

The answer is indeeded +1 D

Statement Break Down : You need to know R. t is already know at 3 years

Statement 1 : D(1) : 11,000

Thus you can easily find out 'R' by equating D(1) & the eqn of D(t)

Thus sufficient

Statement 2 : R know hence sufficient

Thus we can find R which is the
User avatar
Manager
Manager
Joined: 25 Nov 2011
Posts: 126
Own Kudos [?]: 870 [0]
Given Kudos: 20
Location: India
Concentration: Technology, General Management
GPA: 3.95
WE:Information Technology (Computer Software)
Send PM
Re: $10,000 is deposited in a certain account that pays r percent annual [#permalink]
Bunuel wrote:
quantum wrote:
10. $10,000 is deposited in a certain account that pays r percent annual interest compounded annually, the amount D(t), in dollars, that the deposit will grow to in t years in given by D(t)=10,000(1+(r/100))t What amount will the deposit grow to in 3 years?

(1) D(t) = 11,000
(2) r=10

Can anybody explain the logic please?
Thank you!


Two things:
Formula should be \(D(t)=10,000(1+\frac{r}{100})^t\) and statement (1) should read \(D(1)=11,000\) (since two statements in DS never contradict and give true information then r=10 must give 11,000 for t=1 as it does). So the question should read:

$10,000 is deposited in a certain account that pays r percent annual interest compounded annually, the amount D(t), in dollars, that the deposit will grow to in t years in given by D(t)=10,000(1+(r/100))^t What amount will the deposit grow to in 3 years?

Question: \(D(3)=10,000(1+\frac{r}{100})^3=?\). Basically the only thing we need is the value of \(r\).

(1) D(1) = 11,000 --> \(D(1)=10,000(1+\frac{r}{100})^1=11,000\) --> we can solve for r. Sufficient.

(2) r=10 --> directly gives the value of r. Sufficient.

Answer: D.

Hope it's clear.


Agreed. But taking it on the face value, Statement 1 can give an impression that, for any value of t, D(t) gives 11000 ,which I think is not correct. Personally I don;t accept this statement, because in DS category, I do following activities:
1. Is the statement is supported for all situations by the premises/facts given in the question stem.
2. Once the answer for the above is Yes, then I will think, does the statement support all situations of the question.

In this exercise, I get a 'No' to the first part from the question. Hence, the answer should be B.

But, as the statement 1, does not hold good on its face value, I just tried mapping it to the question stem for specific scenario and then got the answer D.

Isn't this correct approach?
Math Expert
Joined: 02 Sep 2009
Posts: 92914
Own Kudos [?]: 618967 [0]
Given Kudos: 81595
Send PM
Re: $10,000 is deposited in a certain account that pays r percent annual [#permalink]
Expert Reply
Chembeti wrote:
Bunuel wrote:
quantum wrote:
10. $10,000 is deposited in a certain account that pays r percent annual interest compounded annually, the amount D(t), in dollars, that the deposit will grow to in t years in given by D(t)=10,000(1+(r/100))t What amount will the deposit grow to in 3 years?

(1) D(t) = 11,000
(2) r=10

Can anybody explain the logic please?
Thank you!


Two things:
Formula should be \(D(t)=10,000(1+\frac{r}{100})^t\) and statement (1) should read \(D(1)=11,000\) (since two statements in DS never contradict and give true information then r=10 must give 11,000 for t=1 as it does). So the question should read:

$10,000 is deposited in a certain account that pays r percent annual interest compounded annually, the amount D(t), in dollars, that the deposit will grow to in t years in given by D(t)=10,000(1+(r/100))^t What amount will the deposit grow to in 3 years?

Question: \(D(3)=10,000(1+\frac{r}{100})^3=?\). Basically the only thing we need is the value of \(r\).

(1) D(1) = 11,000 --> \(D(1)=10,000(1+\frac{r}{100})^1=11,000\) --> we can solve for r. Sufficient.

(2) r=10 --> directly gives the value of r. Sufficient.

Answer: D.

Hope it's clear.


Agreed. But taking it on the face value, Statement 1 can give an impression that, for any value of t, D(t) gives 11000 ,which I think is not correct. Personally I don;t accept this statement, because in DS category, I do following activities:
1. Is the statement is supported for all situations by the premises/facts given in the question stem.
2. Once the answer for the above is Yes, then I will think, does the statement support all situations of the question.

In this exercise, I get a 'No' to the first part from the question. Hence, the answer should be B.

But, as the statement 1, does not hold good on its face value, I just tried mapping it to the question stem for specific scenario and then got the answer D.

Isn't this correct approach?


If we take (1) as it was written: D(t) = 11,000 then it would mean that D(t) has the same value no matter the time period and annual interest, which makes no sense at all. Though technically it still would be sufficient as it would mean that for t=3 the answer is also 11,000.

Having said that I recommend not to spend time on flawed version of a question as you won't see such one on the real test.
User avatar
Manager
Manager
Joined: 25 Nov 2011
Posts: 126
Own Kudos [?]: 870 [0]
Given Kudos: 20
Location: India
Concentration: Technology, General Management
GPA: 3.95
WE:Information Technology (Computer Software)
Send PM
Re: $10,000 is deposited in a certain account that pays r percent annual [#permalink]
Bunuel wrote:

Having said that I recommend not to spend time on flawed version of a question as you won't see such one on the real test.


Sure. I was just thinking whether such questions would appear in a real test, now my doubt is cleared :)
Math Expert
Joined: 02 Sep 2009
Posts: 92914
Own Kudos [?]: 618967 [0]
Given Kudos: 81595
Send PM
Re: $10,000 is deposited in a certain account that pays r percent annual [#permalink]
Expert Reply
Bumping for review and further discussion*. Get a kudos point for an alternative solution!

*New project from GMAT Club!!! Check HERE

Theory on Percent and Interest Problems: math-number-theory-percents-91708.html

All DS Percent and Interest Problems to practice: search.php?search_id=tag&tag_id=33
All PS Percent and Interest Problems to practice: search.php?search_id=tag&tag_id=54
GMAT Club Legend
GMAT Club Legend
Joined: 08 Jul 2010
Status:GMAT/GRE Tutor l Admission Consultant l On-Demand Course creator
Posts: 5960
Own Kudos [?]: 13387 [0]
Given Kudos: 124
Location: India
GMAT: QUANT+DI EXPERT
Schools: IIM (A) ISB '24
GMAT 1: 750 Q51 V41
WE:Education (Education)
Send PM
Re: $10,000 is deposited in a certain account that pays r percent annual [#permalink]
Expert Reply
quantum wrote:
$10,000 is deposited in a certain account that pays r percent annual interest compounded annually, the amount D(t), in dollars, that the deposit will grow to in t years in given by D(t)=10,000(1+(r/100))^t. What amount will the deposit grow to in 3 years?

(1) D(1) = 11,000
(2) r=10



Deposit amount to be calculated by formula D(t)=10,000(1+(r/100))^t

The time = 3 years given

Question: The deposit amount after 3 years = ?

All we need to answer this question is the RATE at which the amount is growing over time.

Statement 1: D(1) = 11,000

i.e. amount after 1 year becomes 11000 from 10000 i.e. rate of growth per year = 10%

SUFFICIENT

Statement 2: r = 10

SUFFICIENT

Answer: option D
User avatar
Non-Human User
Joined: 09 Sep 2013
Posts: 32673
Own Kudos [?]: 821 [0]
Given Kudos: 0
Send PM
Re: $10,000 is deposited in a certain account that pays r percent annual [#permalink]
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 Club Bot
Re: $10,000 is deposited in a certain account that pays r percent annual [#permalink]
Moderator:
Math Expert
92914 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne