NEW HERE? LEARN MORE
close
It is currently 25 Mar 2023, 15:44
Register
GMAT Club Tests
Decision Tracker
My Rewards
New posts
New comers' posts

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

The population of a bacteria colony doubles every day. If it was start

24 posts Go to First Unread Post
Print view
NEW TOPIC
POST REPLY
Downloads
My Bookmarks
Reviews
SORT BY:
Date
Kudos
   1   2 
User avatar
S
thefibonacci
Manager
Manager
Joined: 22 Jan 2014
Posts: 140
WE:Project Management (Computer Hardware)
Re: The population of a bacteria colony doubles every day. If it was start [#permalink] New post  12 Jul 2018, 07:45
WishMasterUA wrote:
The population of a bacteria colony doubles every day. If it was started 9 days ago with 2 bacteria and each bacteria lives for 12 days, how large is the colony today?

A. 512
B. 768
C. 1024
D. 2048
E. 4096

Show Spoiler
My wrong think:

If we have 2 bacteria in first day than it will 2 bacteria in first day. In second day 2*2 or 2^2, so if ^2=2 days than 9 days will be ^9. So my answer is 2^9 or 512.

Help to undestand why we shoul take 2*2^9.

Thanks


M06-18


t-9 -> 2
t-8 -> 4
t-7 -> 8
t-6 -> 16
t-5 -> 32
t-4 -> 64
t-3 -> 128
t-2 -> 256
t-1 -> 512
t-0 -> 1024

hope it is clear.
_________________
Illegitimi non carborundum.
Signature Read More
User avatar
L
Kinshook
GMAT Club Legend
GMAT Club Legend
Joined: 03 Jun 2019
Posts: 4990
Location: India
Schools: HBS '22 CBS '22 Wharton '22
GMAT 1: 690 Q50 V34
WE:Engineering (Transportation)
Reviews Badge
Re: The population of a bacteria colony doubles every day. If it was start [#permalink] New post  22 Aug 2019, 03:55
WishMasterUA wrote:
The population of a bacteria colony doubles every day. If it was started 9 days ago with 2 bacteria and each bacteria lives for 12 days, how large is the colony today?

A. 512
B. 768
C. 1024
D. 2048
E. 4096

Show Spoiler
My wrong think:

If we have 2 bacteria in first day than it will 2 bacteria in first day. In second day 2*2 or 2^2, so if ^2=2 days than 9 days will be ^9. So my answer is 2^9 or 512.

Help to undestand why we shoul take 2*2^9.

Thanks


M06-18


Given:
1. The population of a bacteria colony doubles every day.
2. It was started 9 days ago with 2 bacteria and each bacteria lives for 12 days

Asked: How large is the colony today?

1. The population of a bacteria colony doubles every day.
2. It was started 9 days ago with 2 bacteria and each bacteria lives for 12 days

Nine days ago population was of bacteria was = 2
Today is tenth day, population of bacteria today = 2^10 = 1024

IMO C
_________________
Kinshook Chaturvedi
Email: kinshook.chaturvedi@gmail.com
Signature Read More
User avatar
L
MathRevolution
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 11491
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: The population of a bacteria colony doubles every day. If it was start [#permalink] New post  19 Nov 2020, 10:19
9 days ago from today will be a total of 10 days.

Bacteria population: \(2^10\) = 1024

Answer C
_________________
MathRevolution: The World's Most "Complete" GMAT Math Course!
Score an excellent Q49-51 just like 70% of our students.
[Free] On-demand trial course (7 days) - 100 hours of video lessons, 490 lesson topics, and 2,000 questions.
[Course] Starting at $79 for on-demand and $60 for tutoring per hour
Signature Read More
User avatar
bumpbot
Non-Human User
Joined: 09 Sep 2013
Posts: 27102
Re: The population of a bacteria colony doubles every day. If it was start [#permalink] New post  15 Dec 2021, 00:03
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.
_________________
GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources
Signature Read More
GMAT Club Bot
gmatclubot
Re: The population of a bacteria colony doubles every day. If it was start [#permalink]
15 Dec 2021, 00:03
NEW TOPIC
POST REPLY
Downloads
My Bookmarks
Reviews
   1   2 
Moderators:
chetan2u
Math Expert
10528 posts
Bunuel
Math Expert
88642 posts
yashikaaggarwal
Senior Moderator - Masters Forum
3143 posts

cron

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne
Main navigation
GMAT Resources
Partners
MBA Resources
www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions