Last visit was: 25 Apr 2026, 21:58 It is currently 25 Apr 2026, 21:58
Home
Messages
Tests
Schools
Events
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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel
Back to Forum
Create Topic
805+ (Hard)|   Word Problems|      
User avatar
Jihyo
User avatar
Joined: 01 Apr 2021
Last visit: 06 Mar 2022
Posts: 53
Own Kudos:
221
 [8]
Given Kudos: 166
Posts: 53
Kudos: 221
 [8]
The population of a country increased by an average of 1% per year 04 May 2021, 08:27
1
Kudos
Add Kudos
7
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
B
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

95% (hard)

Question Stats:

41% (02:31) correct 59% (02:28) wrong based on 145 sessions

History

Date
Time
Result
Not Attempted Yet
The population of a country increased by an average of 1% per year from 2016 to 2019 .If the population of the country was 21 million on December 31,2019,then the population of this country on January 1,2016 ,to the nearest thousand had been:

A. 20400
B. 20200
C. 20000
D. 18000
E. 15000
ShowHide Answer
Official Answer
B
User avatar
MarmikUpadhyay
User avatar
Scoreleap Test Prep Representative
Joined: 08 Mar 2021
Last visit: 11 Nov 2021
Posts: 217
Own Kudos:
156
 [5]
Expert
Expert reply
Posts: 217
Kudos: 156
 [5]
The population of a country increased by an average of 1% per year 04 May 2021, 22:09
2
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
Jihyo
The population of a country increased by an average of 1% per year from 2016 to 2019 .If the population of the country was 21 million on December 31,2019,then the population of this country on January 1,2016 ,to the nearest thousand had been:
A)20400
B)20200
C)20000
D)18000
E)15000
Show more

Let population on January 1, 2016 = x =?, Population increases by 1% per annum, Population on December 31, 2019 = 21 million.

Population on January 1, 2017 = 1.01 * x
Population on January 1, 2018 = 1.01 * (1.01 * x) = \(1.01^2\) * x
Population on January 1, 2019 = \(1.01^3\) * x
Population on January 1, 2020 = Population on December 31, 2019 = \(1.01^4\) * x = 21,000,000

=> x = \(\frac{21,000,000}{1.01^4}\) = 20,180,000 \(\approx\) 20,200 thousand

So, correct answer is option B.
avatar
adilaahsanprita
avatar
Joined: 10 Apr 2021
Last visit: 11 Oct 2021
Posts: 3
Own Kudos:
2
 [2]
Given Kudos: 24
Posts: 3
Kudos: 2
 [2]
The population of a country increased by an average of 1% per year 10 Oct 2021, 07:04
2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hey! How to shorten this calculation since we wont be able to use calculator;-;

Posted from my mobile device
avatar
shohan2722
avatar
Joined: 16 Jan 2022
Last visit: 01 Sep 2022
Posts: 9
Own Kudos:
6
 [2]
Given Kudos: 25
Posts: 9
Kudos: 6
 [2]
The population of a country increased by an average of 1% per year 12 May 2022, 07:02
1
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
MarmikUpadhyay
Jihyo
The population of a country increased by an average of 1% per year from 2016 to 2019 .If the population of the country was 21 million on December 31,2019,then the population of this country on January 1,2016 ,to the nearest thousand had been:
A)20400
B)20200
C)20000
D)18000
E)15000

Let population on January 1, 2016 = x =?, Population increases by 1% per annum, Population on December 31, 2019 = 21 million.

Population on January 1, 2017 = 1.01 * x
Population on January 1, 2018 = 1.01 * (1.01 * x) = \(1.01^2\) * x
Population on January 1, 2019 = \(1.01^3\) * x
Population on January 1, 2020 = Population on December 31, 2019 = \(1.01^4\) * x = 21,000,000

=> x = \(\frac{21,000,000}{1.01^4}\) = 20,180,000 \(\approx\) 20,200 thousand

So, correct answer is option B.
Show more
Any way to simplify the calculation
User avatar
Jxmes
User avatar
Joined: 26 Jul 2018
Last visit: 25 Apr 2026
Posts: 17
Own Kudos:
3
Given Kudos: 12
Posts: 17
Kudos: 3
The population of a country increased by an average of 1% per year 02 Nov 2024, 13:16
Kudos
Add Kudos
Bookmarks
Bookmark this Post
work backward from 2019
shohan2722
MarmikUpadhyay
Jihyo
The population of a country increased by an average of 1% per year from 2016 to 2019 .If the population of the country was 21 million on December 31,2019,then the population of this country on January 1,2016 ,to the nearest thousand had been:
A)20400
B)20200
C)20000
D)18000
E)15000

Let population on January 1, 2016 = x =?, Population increases by 1% per annum, Population on December 31, 2019 = 21 million.

Population on January 1, 2017 = 1.01 * x
Population on January 1, 2018 = 1.01 * (1.01 * x) = \(1.01^2\) * x
Population on January 1, 2019 = \(1.01^3\) * x
Population on January 1, 2020 = Population on December 31, 2019 = \(1.01^4\) * x = 21,000,000

=> x = \(\frac{21,000,000}{1.01^4}\) = 20,180,000 \(\approx\) 20,200 thousand

So, correct answer is option B.
Any way to simplify the calculation
Show more
Moderators:
Bunuel
Math Expert
109830 posts
Krunaal
Tuck School Moderator
852 posts