The population of a bacteria culture doubles every 2 minutes : GMAT Problem Solving (PS)
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 24 Jan 2017, 03:49

### 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 June
Open Detailed Calendar

# The population of a bacteria culture doubles every 2 minutes

Author Message
TAGS:

### Hide Tags

Director
Joined: 10 Feb 2006
Posts: 658
Followers: 3

Kudos [?]: 461 [1] , given: 0

The population of a bacteria culture doubles every 2 minutes [#permalink]

### Show Tags

13 Mar 2008, 19:39
1
KUDOS
11
This post was
BOOKMARKED
00:00

Difficulty:

45% (medium)

Question Stats:

64% (01:56) correct 36% (01:06) wrong based on 279 sessions

### HideShow timer Statistics

The population of a bacteria culture doubles every 2 minutes. Approximately how many minutes will it take for the population to grow from 1,000 to 500,000 bacteria

A. 10
B. 12
C. 14
D. 16
E. 18

OPEN DISCUSSION OF THIS QUESTION IS HERE: the-population-of-a-bacteria-culture-doubles-every-2-minutes-167378.html
[Reveal] Spoiler: OA

_________________

GMAT the final frontie!!!.

Last edited by Bunuel on 25 Jun 2014, 08:49, edited 2 times in total.
Renamed the topic, edited the question, added the OA and moved to PS forum.
Intern
Joined: 12 Mar 2008
Posts: 4
Followers: 0

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

Re: The population of a bacteria culture doubles every 2 minutes [#permalink]

### Show Tags

13 Mar 2008, 21:42
Is not quite that.
min 0 - 1,000
min 2 - 2,000=1,000*2^1
min 4 - 4000=1000*2^2;
min 6 - 8000=1000*2^3

Be careful! It doubles every 2 minutes.

So, 1,000*2^x=500,000
2^x=500. It asks you to approx. You know that 2^9=512, so x=9.
Because the pop doubles every 2 minutes, the result=9*2=18 minutes.
OA?
Current Student
Joined: 06 Sep 2013
Posts: 2035
Concentration: Finance
GMAT 1: 770 Q0 V
Followers: 62

Kudos [?]: 594 [5] , given: 355

Re: The population of a bacteria culture doubles every 2 minutes [#permalink]

### Show Tags

11 Sep 2013, 17:13
5
KUDOS
This one's easy.

1000 * 2^t = 500,000
2^t = 500
Now gauging, since 2^8 = 256, then 2^9 = 512
So t = 9

But be careful, 't' is in time intervals of two minutes

So answer is 9*2 = 18 minutes

Math Expert
Joined: 02 Sep 2009
Posts: 36625
Followers: 7103

Kudos [?]: 93622 [0], given: 10583

Re: The population of a bacteria culture doubles every 2 minutes [#permalink]

### Show Tags

12 Sep 2013, 01:26
Expert's post
5
This post was
BOOKMARKED
The population of a bacteria culture doubles every 2 minutes. Approximately how many minutes will it take for the population to grow from 1,000 to 500,000 bacteria

A. 10
B. 12
C. 14
D. 16
E. 18

Similar questions to practice:
a-certain-bacteria-colony-doubles-in-size-every-day-for-144013.html
it-takes-30-days-to-fill-a-laboratory-dish-with-bacteria-140269.html
the-number-of-water-lilies-on-a-certain-lake-doubles-every-142858.html
_________________
Math Expert
Joined: 02 Sep 2009
Posts: 36625
Followers: 7103

Kudos [?]: 93622 [0], given: 10583

The population of a bacteria culture doubles every 2 minutes [#permalink]

### Show Tags

25 Jun 2014, 08:50
Expert's post
2
This post was
BOOKMARKED
The population of a bacteria culture doubles every 2 minutes. Approximately how many minutes will it take for the population to grow from 1,000 to 500,000 bacteria?

(A) 10
(B) 12
(C) 14
(D) 16
(E) 18

$$1000 * 2^t = 500,000$$ --> $$2^t = 500$$ --> since $$2^9 = 512$$, then $$t\approx{9}$$. Thus, approximately 9 two-minute intervals are needed, whcih is 18 minutes.

Similar questions to practice:
a-certain-bacteria-colony-doubles-in-size-every-day-for-144013.html
it-takes-30-days-to-fill-a-laboratory-dish-with-bacteria-140269.html
the-number-of-water-lilies-on-a-certain-lake-doubles-every-142858.html
the-population-of-locusts-in-a-certain-swarm-doubles-every-90353.html

OPEN DISCUSSION OF THIS QUESTION IS HERE: the-population-of-a-bacteria-culture-doubles-every-2-minutes-167378.html
_________________
The population of a bacteria culture doubles every 2 minutes   [#permalink] 25 Jun 2014, 08:50
Similar topics Replies Last post
Similar
Topics:
9 A certain population of bacteria doubles every 10 minutes. If the numb 7 03 Dec 2014, 07:23
27 The population of a bacteria culture doubles every 2 minutes 14 11 Feb 2014, 00:00
10 A certain population of bacteria doubles every 10 minutes. 6 05 Jan 2014, 12:05
4 The population of a bacteria colony doubles every day. If it was start 18 04 Jun 2011, 02:53
The population of a bacteria culture doubles every 2 minutes. Approxim 1 17 Feb 2011, 03:26
Display posts from previous: Sort by