It is currently 12 Dec 2017, 03:34

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

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

John received a 10% raise each month for three consecutive months. Wha

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 42560

Kudos [?]: 135317 [0], given: 12686

John received a 10% raise each month for three consecutive months. Wha [#permalink]

Show Tags

New post 10 Jan 2016, 08:27
00:00
A
B
C
D
E

Difficulty:

  5% (low)

Question Stats:

97% (00:42) correct 3% (00:37) wrong based on 72 sessions

HideShow timer Statistics

John received a 10% raise each month for three consecutive months. What was his salary after the three raises if his starting salary was $1,000 per month?

A. $1,248
B. $1,300
C. $1,331
D. $1,410
E. $1,463
[Reveal] Spoiler: OA

_________________

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?
Extra-hard Quant Tests with Brilliant Analytics

Kudos [?]: 135317 [0], given: 12686

Intern
Intern
avatar
Joined: 29 Dec 2015
Posts: 10

Kudos [?]: 2 [0], given: 1

GPA: 2.8
Re: John received a 10% raise each month for three consecutive months. Wha [#permalink]

Show Tags

New post 10 Jan 2016, 08:42
1,000 + 100 (10%) = 1,100
1,100 + 110 (10%) = 1,210
1,210 + 121 (10%) = 1,331

Ans C

Kudos [?]: 2 [0], given: 1

Director
Director
User avatar
S
Joined: 24 Nov 2015
Posts: 585

Kudos [?]: 40 [0], given: 231

Location: United States (LA)
Reviews Badge CAT Tests
Re: John received a 10% raise each month for three consecutive months. Wha [#permalink]

Show Tags

New post 16 May 2016, 13:25
1000 * 1.1 * 1.1 * 1.1 = 1000 * 1.331 = 1331
Correct answer - C

Kudos [?]: 40 [0], given: 231

Manager
Manager
avatar
G
Joined: 04 Jan 2016
Posts: 165

Kudos [?]: 73 [0], given: 419

Location: Afganistan
GMAT 1: 620 Q44 V32
GMAT 2: 600 Q48 V25
GMAT 3: 660 Q42 V39
GPA: 3.48
GMAT ToolKit User Premium Member
John received a 10% raise each month for three consecutive months. Wha [#permalink]

Show Tags

New post 28 May 2017, 19:08
We can consider the 10 percent increase as of following: \(\frac{11}{10} *\frac{11}{10}*\frac{11}{0} or (\frac{11}{10})^3\)


\((\frac{11}{10}*\frac{11}{10}*\frac{11}{10})*1000=1331\)

The correct option: C

Kudos [?]: 73 [0], given: 419

Manager
Manager
User avatar
G
Joined: 30 May 2012
Posts: 218

Kudos [?]: 84 [0], given: 151

Location: United States (TX)
Concentration: Finance, Marketing
GPA: 3.3
WE: Information Technology (Consulting)
Premium Member
Re: John received a 10% raise each month for three consecutive months. Wha [#permalink]

Show Tags

New post 04 Sep 2017, 21:51
Bunuel - How can I apply this consecutive interest/rate changes formula below to problems like this?

a+b+\(\frac{ab}{100}\). Or is it that this formula applies only when there are two consecutive rate/interest changes? TIA.

Kudos [?]: 84 [0], given: 151

Intern
Intern
avatar
B
Joined: 10 Jul 2017
Posts: 30

Kudos [?]: 6 [0], given: 51

CAT Tests
Re: John received a 10% raise each month for three consecutive months. Wha [#permalink]

Show Tags

New post 04 Sep 2017, 22:12
Bunuel wrote:
John received a 10% raise each month for three consecutive months. What was his salary after the three raises if his starting salary was $1,000 per month?

A. $1,248
B. $1,300
C. $1,331
D. $1,410
E. $1,463



My answer is C- 1331.

We can apply the concept of CI as the 10% raise each month is on the salary of that month. And each month's salary includes last month's salary plus the 10% hike.

Thus, applying CI formula,
Amount = P[1+(10/100)]^3
= 1000(11/10)^ 3 = 1331.




Sent from my iPhone using GMAT Club Forum mobile app

Kudos [?]: 6 [0], given: 51

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 42560

Kudos [?]: 135317 [0], given: 12686

Re: John received a 10% raise each month for three consecutive months. Wha [#permalink]

Show Tags

New post 04 Sep 2017, 23:50
Blackbox wrote:
Bunuel - How can I apply this consecutive interest/rate changes formula below to problems like this?

a+b+\(\frac{ab}{100}\). Or is it that this formula applies only when there are two consecutive rate/interest changes? TIA.


Yes, \(a+b+\frac{ab}{100}\) gives the effective percentage change over TWO periods, not three. So, for this problem if it were "...for TWO consecutive months...", then the effective percentage change would be \(a+b+\frac{ab}{100}=10+10+\frac{100}{100}=21\%\). But you can find it directly with 1.1^2 = 1.21. So, you should use this formula if there are two periods and a and b are different from each other.

For more check "Successive Percentage Changes" chapter in Percentages, Interest and More.

Hope it helps.
_________________

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?
Extra-hard Quant Tests with Brilliant Analytics

Kudos [?]: 135317 [0], given: 12686

Intern
Intern
avatar
B
Joined: 04 Oct 2016
Posts: 9

Kudos [?]: [0], given: 3

Re: John received a 10% raise each month for three consecutive months. Wha [#permalink]

Show Tags

New post 05 Sep 2017, 00:41
Bunuel wrote:
John received a 10% raise each month for three consecutive months. What was his salary after the three raises if his starting salary was $1,000 per month?

A. $1,248
B. $1,300
C. $1,331
D. $1,410
E. $1,463

1,000*1.1^3=1,331
Answer C

Kudos [?]: [0], given: 3

Manager
Manager
User avatar
G
Joined: 30 May 2012
Posts: 218

Kudos [?]: 84 [0], given: 151

Location: United States (TX)
Concentration: Finance, Marketing
GPA: 3.3
WE: Information Technology (Consulting)
Premium Member
John received a 10% raise each month for three consecutive months. Wha [#permalink]

Show Tags

New post 05 Sep 2017, 06:30
Bunuel wrote:
Blackbox wrote:
Bunuel - How can I apply this consecutive interest/rate changes formula below to problems like this?

a+b+\(\frac{ab}{100}\). Or is it that this formula applies only when there are two consecutive rate/interest changes? TIA.


Yes, \(a+b+\frac{ab}{100}\) gives the effective percentage change over TWO periods, not three. So, for this problem if it were "...for TWO consecutive months...", then the effective percentage change would be \(a+b+\frac{ab}{100}=10+10+\frac{100}{100}=21\%\). But you can find it directly with 1.1^2 = 1.21. So, you should use this formula if there are two periods and a and b are different from each other.

For more check "Successive Percentage Changes" chapter in Percentages, Interest and More.

Hope it helps.


Thank you for the explanation.

Kudos [?]: 84 [0], given: 151

Expert Post
Target Test Prep Representative
User avatar
S
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 1922

Kudos [?]: 1012 [0], given: 3

Location: United States (CA)
Re: John received a 10% raise each month for three consecutive months. Wha [#permalink]

Show Tags

New post 07 Sep 2017, 16:48
Bunuel wrote:
John received a 10% raise each month for three consecutive months. What was his salary after the three raises if his starting salary was $1,000 per month?

A. $1,248
B. $1,300
C. $1,331
D. $1,410
E. $1,463


John’s salary after 3 months is 1000(11/10)(11/10)(11/10) = 11 x 11 x 11 = $1331.

Answer: C
_________________

Scott Woodbury-Stewart
Founder and CEO

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Kudos [?]: 1012 [0], given: 3

Re: John received a 10% raise each month for three consecutive months. Wha   [#permalink] 07 Sep 2017, 16:48
Display posts from previous: Sort by

John received a 10% raise each month for three consecutive months. Wha

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

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

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.