GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 15 Nov 2018, 15:36

### 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

## Events & Promotions

###### Events & Promotions in November
PrevNext
SuMoTuWeThFrSa
28293031123
45678910
11121314151617
18192021222324
2526272829301
Open Detailed Calendar
• ### Free GMAT Strategy Webinar

November 17, 2018

November 17, 2018

07:00 AM PST

09:00 AM PST

Nov. 17, 7 AM PST. Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT.
• ### GMATbuster's Weekly GMAT Quant Quiz # 9

November 17, 2018

November 17, 2018

09:00 AM PST

11:00 AM PST

Join the Quiz Saturday November 17th, 9 AM PST. The Quiz will last approximately 2 hours. Make sure you are on time or you will be at a disadvantage.

# What was the percent increase in population of City K from

Author Message
TAGS:

### Hide Tags

Director
Joined: 01 May 2007
Posts: 772
What was the percent increase in population of City K from  [#permalink]

### Show Tags

24 Mar 2008, 12:41
9
28
00:00

Difficulty:

15% (low)

Question Stats:

75% (01:02) correct 25% (00:50) wrong based on 901 sessions

### HideShow timer Statistics

What was the percent increase in population of City K from 1980 to 1990?

1) In 1970 the population of City K was 160,000
2) In 1980 the population of City K was 20% greater than it was in 1970, and in 1990 the population of City K was 30% greater than it was in 1970.
Director
Joined: 10 Sep 2007
Posts: 887
Re: What was the percent increase in population of City K from  [#permalink]

### Show Tags

24 Mar 2008, 13:57
11
6
Statement 1:
Tells us about population in 1970 and nothing else, so this alone is insufficient.

Statement 2:
Tells us that in 1980 population is 20% more than it was in 1970. Say it was x in 1970, then in 1980 it is 1.2x.
Also given that in 1990 population is 30% more than it was in 1970. Say it was x in 1970, then in 1990 it is 1.3x.

Percent Increase from 1980 to 1990 = (1.3x-1.2x)*100/1.2x (Although you don't need to calcluate it, as answer is not required to be filled in anywhere.

##### General Discussion
Director
Status: No dream is too large, no dreamer is too small
Joined: 14 Jul 2010
Posts: 532
Re: What was the percent increase in population of City K from  [#permalink]

### Show Tags

28 Jun 2011, 10:07
4
Let the population of 1970 = 100
so population of 1980 = 120
thus population of 1990 = 130
percentage increase = 10/120*100
ans.D
_________________

Collections:-
PSof OG solved by GC members: http://gmatclub.com/forum/collection-ps-with-solution-from-gmatclub-110005.html
DS of OG solved by GC members: http://gmatclub.com/forum/collection-ds-with-solution-from-gmatclub-110004.html
100 GMAT PREP Quantitative collection http://gmatclub.com/forum/gmat-prep-problem-collections-114358.html
Collections of work/rate problems with solutions http://gmatclub.com/forum/collections-of-work-rate-problem-with-solutions-118919.html
Mixture problems in a file with best solutions: http://gmatclub.com/forum/mixture-problems-with-best-and-easy-solutions-all-together-124644.html

Director
Joined: 01 Feb 2011
Posts: 664
Re: What was the percent increase in population of City K from  [#permalink]

### Show Tags

28 Jun 2011, 15:10
1
((90 - 80 )/ 80 )*100

1. Not sufficient

we dont know anything about 80 or 90.

2. Sufficient

70 80 90
x 120x/100 130x/100

from this we can easily find out ((80-90)/80 )*100

Manager
Joined: 28 Feb 2011
Posts: 63
Re: What was the percent increase in population of City K from  [#permalink]

### Show Tags

28 Jun 2011, 17:51
1
1
B..
Let population in 1970=100
Then, in 1980= 120
in 1990= 130

We can easily find the percent increase from 1980 to 1990 now..
_________________

Fight till you succeed like a gladiator..or doom your life which can be invincible

Intern
Joined: 12 Jul 2016
Posts: 18
Re: What was the percent increase in population of City K from  [#permalink]

### Show Tags

08 May 2017, 02:45
Statement 1 is clearly unsufficient since there is no information about 1980 nor 1990.
Statement 2 ables to deduce the solution but only if we have the 1970's population. (unsufficient)
Manager
Joined: 17 May 2017
Posts: 131
GPA: 3
Re: What was the percent increase in population of City K from  [#permalink]

### Show Tags

18 Jul 2017, 11:07
1
This is a GMATPrep Question
Someone edit the tag
Math Expert
Joined: 02 Sep 2009
Posts: 50613
Re: What was the percent increase in population of City K from  [#permalink]

### Show Tags

18 Jul 2017, 11:10
1
haardiksharma wrote:
This is a GMATPrep Question
Someone edit the tag

-__________
Edited. Thank you.
_________________
Non-Human User
Joined: 09 Sep 2013
Posts: 8772
Re: What was the percent increase in population of City K from  [#permalink]

### Show Tags

23 Jul 2018, 05:36
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.
_________________
Re: What was the percent increase in population of City K from &nbs [#permalink] 23 Jul 2018, 05:36
Display posts from previous: Sort by