BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Target Test Prep · GMAT

Choose how you want to prepare

Learn live with an expert or move at your own pace. Every option includes the complete TTP study system.

★★★★★5.0559 reviews
GMATLiveTeach 7 seats left
Chris Peckover
NEXT LIVE COHORT

Oct 13 to Jan 7, 2027

with Chris Peckover

Schedule
Tue, Thu · 8:00 to 10:00 PM ET
Included
40 live hours + 6 months of GMAT OnDemand
  • Live instruction and real-time questions
  • Class recordings and assigned practice
View class & enroll
Limited cohort · enrollment openTarget Test Prep
EALiveTeach 5 seats left
Logan Thompson
EXECUTIVE ASSESSMENT

Sep 6 to Dec 6, 2026

with Logan Thompson

Schedule
Sun · 9:30 AM to 12:30 PM ET
Included
40 hours of live online classes plus six months of access to the complete TTP EA OnDemand course.
  • 165+ EA Score Guarantee
  • 4,100+ Quant, Verbal, and Integrated Reasoning practice questions
  • 400+ hours of in-depth video lessons
  • 3,000+ step-by-step video solutions
View EA class & enroll
Limited cohort · enrollment openTarget Test Prep
GMATOnDemand Start anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

715+ score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions
Start free 5-day trial
Read 559 reviewsTarget Test Prep

Compare the format, schedule, and included access before enrolling. Prices and seat counts shown reflect the supplied offer details.

GMATPrep - If $1000 is deposited in a certain bank

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Source: — Data Sufficiency |
Legendary Member
Posts: 2467
Joined: Thu Aug 28, 2008 6:14 pmFollowed by: 11 members
Thanked: 331 times

by cramya » Mon Nov 03, 2008 5:46 pm
Stmt I)

1000 ( (1+r/100) ^ 2 ) - 1) = 210

One eqn one variable we can easily find r (1 SPECIFIC INTEREST RATE) and tell if interest iS greater than 8 or not. No need to solve just knowing that this is sufficient to get to a definite answer will do


SUFF

Stmt II)

(1+r/100) ^ 2 > 1.15

Taking square root on both sides

1+r/100 > sqrt(1.15) (between 1.07 and 1.08 definitely not 1.08 sicne it will be bigger and here otself we know it will be r > 7.something)

r/100 >1.075(approx) - 1
r>7.5...

INSUFF

COULD BE 9 , 19, 7.6 ANYTHING

INSUFF

A)
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 203
Joined: Wed Jun 04, 2008 1:01 am
Location: Windsor
Thanked: 5 times
GMAT Score:650

by jsl » Tue Nov 04, 2008 2:02 am
cramya wrote:sqrt(1.15) (between 1.07 and 1.08 definitely not 1.08 sicne it will be bigger and here otself we know it will be r > 7.something)
Thanks for your help. Can you elaborate a bit more on how you were able to quickly evaluate sqrt(1.15) - can you take me through the steps?
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 103
Joined: Mon May 04, 2009 11:53 am
Thanked: 6 times

by navalpike » Sun Aug 02, 2009 6:43 pm
How could Cramya possibly know what the square root of 1.15 is?

Can anyone show another way to eliminate S2?

Thanks,
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Legendary Member
Posts: 516
Joined: Fri Jul 31, 2009 3:22 pmFollowed by: 13 members
Thanked: 112 times

by smackmartine » Mon Jun 27, 2011 7:41 pm
navalpike wrote:How could Cramya possibly know what the square root of 1.15 is?

Can anyone show another way to eliminate S2?

Thanks,
(1+r/100)^n = (1+[n*r]/100) (approx.) REMEMBER THIS!
So (1+r/100)^2 >1.15
(1+2r/100)> 1.15
2r/100 > 15/100
r>15/2
r>7.5
So, r can be , say, 7.6 or 9 (Insufficient)
Smack is Back ...
It takes time and effort to explain, so if my comment helped you please press Thanks button :)
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Master | Next Rank: 500 Posts
Posts: 134
Joined: Fri Jan 23, 2009 1:23 pmFollowed by: 15 members
Location: California
Thanked: 59 times

by dabral » Tue Jun 28, 2011 11:02 am
Here is a video solution that shows another way to do it without the square root approach:

https://www.gmatquantum.com/shared-posts ... est14.html

Dabral
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
GMAT Instructor
Posts: 15539
Joined: Tue May 25, 2010 12:04 pmFollowed by: 1906 members
Location: New York, NY
Thanked: 13060 times
GMAT Score:790

by GMATGuruNY » Tue Jun 28, 2011 1:07 pm
jsl wrote:If 1,000 is deposited in a certain bank account and remains in the account and any accumulated interest, I, earned by the deposit in the first n years is given by the formula I = 1,000((1 + r/100)^n - 1), where r percent is the annual interest rate paid by the band, is the annual interest rate paid by the bank greater than 8 percent?

1) The deposit earns a total of $210 in interest in the first 2 years
2) (1 + r/100)^2 > 1.15

OA A
Question: Is r > 8?

Statement 1: The deposit earns a total of $210 in interest in the first 2 years.
Plug I=210 and n=2 into the given equation:
210 = 1,000 ((1+r/100)^2 -1)
We can solve for r.
Sufficient.

Statement 2: (1+r/100)^2 > 1.15
Plug in r=8.
(1 + 8/100)² > 115/100
(108/100)² > 115/100
(108*108)/(100*100) > 115/100
(108*108)/100 > 115

Ballpark the left side:
(11,600)/100 > 115
116 > 115.

Since r=8 works, we know that r>8 also works.
Insufficient.

The correct answer is A.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.

As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.

For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Master | Next Rank: 500 Posts
Posts: 235
Joined: Wed Oct 26, 2016 9:21 pmFollowed by: 5 members
Thanked: 3 times

by Anaira Mitch » Mon Jan 30, 2017 4:19 pm
GMATGuruNY wrote:
jsl wrote:If 1,000 is deposited in a certain bank account and remains in the account and any accumulated interest, I, earned by the deposit in the first n years is given by the formula I = 1,000((1 + r/100)^n - 1), where r percent is the annual interest rate paid by the band, is the annual interest rate paid by the bank greater than 8 percent?

1) The deposit earns a total of $210 in interest in the first 2 years
2) (1 + r/100)^2 > 1.15

OA A
Question: Is r > 8?

Statement 1: The deposit earns a total of $210 in interest in the first 2 years.
Plug I=210 and n=2 into the given equation:
210 = 1,000 ((1+r/100)^2 -1)
We can solve for r.
Sufficient.

Statement 2: (1+r/100)^2 > 1.15
Plug in r=8.
(1 + 8/100)² > 115/100
(108/100)² > 115/100
(108*108)/(100*100) > 115/100
(108*108)/100 > 115

Ballpark the left side:
(11,600)/100 > 115
116 > 115.

Since r=8 works, we know that r>8 also works.
Insufficient.

The correct answer is A.
Hello Mitch,

Your solution is perfect but I am confused why this statement is insufficient as you have mentioned
"Since r=8 works, we know that r>8 also works."
Please help me understand.
Thanks in advance.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
GMAT Instructor
Posts: 15539
Joined: Tue May 25, 2010 12:04 pmFollowed by: 1906 members
Location: New York, NY
Thanked: 13060 times
GMAT Score:790

by GMATGuruNY » Tue Jan 31, 2017 5:20 am
Anaira Mitch wrote:
GMATGuruNY wrote:Statement 2: (1+r/100)^2 > 1.15
Plug in r=8.
(1 + 8/100)² > 115/100
(108/100)² > 115/100
(108*108)/(100*100) > 115/100
(108*108)/100 > 115

Ballpark the left side:
(11,600)/100 > 115
116 > 115.

Since r=8 works, we know that r>8 also works.
Insufficient.

The correct answer is A.
Hello Mitch,

Your solution is perfect but I am confused why this statement is insufficient as you have mentioned
"Since r=8 works, we know that r>8 also works."
Please help me understand.
Thanks in advance.
My solution in blue implies the following:
If r=8, then (1+r/100)² ≈ 1.16.

Question stem:
Is r > 8?

Statement 2: (1+r/100)² > 1.15
Case 1: r=8, with the result that (1+r/100)² ≈ 1.16.
In this case, the answer to the question stem is NO.

Case 2: r=9, with the result that (1+r/100)² > 1.16.
In this case, the answer to the question stem is YES.

Since the answer is NO in Case 1 but YES in Case 2, INSUFFICIENT.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.

As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.

For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 3008
Joined: Mon Aug 22, 2016 6:19 amFollowed by: 34 members
Location: Grand Central / New York
Thanked: 470 times

by Jay@ManhattanReview » Tue Jan 31, 2017 9:58 pm
A couple of experts have presented their solutions. They are great. As far as Statement 1 is concerned, there seem to be no issues with regard to the understanding with any.

Statement 2 involves cumbersome calculation to reach the conclusion. So, I focus only on Statement 2.

S2: (1+r/100)^2 > 1.15

We are given that (1+r/100)^2 > 1.15, it means that $1000 would be more than $1150 in 2 years. If we considered (1+r/100)^2 = 1.15, and that the money were on simple interest instead of compound interest, the simple interest rate per annum = 1.5/2 = 7.5.

Since the money is on compounding, the rate in the above scenario must be less than 7.50%. For your interest, it is 7.23%.

So, the rate, r can be anything more than somewhat less than 7.50%.

If ~7.50% < r ≤ 8%, the answer is No.

If r > 8%, the answer is Yes. No unique answer. Insufficient.

Hope this helps!

Relevant book: Manhattan Review GMAT Data Sufficiency Guide

-Jay
_________________
Manhattan Review GMAT Prep

Locations: New York | Frankfurt | Hong Kong | Zurich | and many more...

Schedule your free consultation with an experienced GMAT Prep Advisor! Click here.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1