NEW HERE? LEARN MORE
closeclose
Last visit was: 23 Apr 2024, 20:22 It is currently 23 Apr 2024, 20:22
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

A computer password consists of two letters, which are

User avatar
MA
Director
Director
Joined: 25 Nov 2004
Posts: 707
Own Kudos [?]: 448 [0]
Given Kudos: 0
Send PM
A computer password consists of two letters, which are [#permalink] New post   08 Feb 2005, 23:02
A computer password consists of two letters, which are allowed to be repeated, and three numerical digits. how many passwords can be created?



Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Quantitative Questions Forum
Still interested in this question? Check out the "Best Topics" block below for a better discussion on this exact question, as well as several more related questions.
Thank you for understanding, and happy exploring!
User avatar
Folaa3
Senior Manager
Senior Manager
Joined: 27 Dec 2004
Posts: 383
Own Kudos [?]: 108 [0]
Given Kudos: 0
Send PM
Re: A computer password consists of two letters, which are [#permalink] New post   08 Feb 2005, 23:08
is it 71280.
That is if the number cannot be repeated but the two letters can be repeated
avatar
HongHu
Director
Director
Joined: 03 Jan 2005
Posts: 971
Own Kudos [?]: 769 [0]
Given Kudos: 0
Send PM
Re: A computer password consists of two letters, which are [#permalink] New post   08 Feb 2005, 23:15
26*26*10*10*10 if numbers can be repeated
26*26*10*9*8 otherwise.
User avatar
Vijo
Manager
Manager
Joined: 01 Jan 2005
Posts: 76
Own Kudos [?]: 8 [0]
Given Kudos: 0
Location: NJ
Send PM
Re: A computer password consists of two letters, which are [#permalink] New post   09 Feb 2005, 07:04
HONGHU'S ANSWER IS PERFECT. I AGREE WITH HI ANSWER.
User avatar
banerjeea_98
Director
Director
Joined: 18 Nov 2004
Posts: 679
Own Kudos [?]: 198 [0]
Given Kudos: 0
Send PM
Re: A computer password consists of two letters, which are [#permalink] New post   Updated on: 09 Feb 2005, 12:08
5C3 (10x9x8) *(26*26) = 10 (720)(676) = 4867200 ways..........assuming numbers can't be repeated.

Ques doesn't say that the password should have first 2 as letters and last 3 as numbers, they can be anywhere thus I think we need to multiply by 5C3 = 10 also.

Originally posted by banerjeea_98 on 09 Feb 2005, 10:11.
Last edited by banerjeea_98 on 09 Feb 2005, 12:08, edited 1 time in total.
User avatar
swath20
Manager
Manager
Joined: 25 Oct 2004
Posts: 142
Own Kudos [?]: 285 [0]
Given Kudos: 0
Send PM
Re: A computer password consists of two letters, which are [#permalink] New post   09 Feb 2005, 11:45
Even I agree with Honghu' s answer
avatar
HongHu
Director
Director
Joined: 03 Jan 2005
Posts: 971
Own Kudos [?]: 769 [0]
Given Kudos: 0
Send PM
Re: A computer password consists of two letters, which are [#permalink] New post   09 Feb 2005, 12:28
banerjeea_98 wrote:
5C3 (10x9x8) *(26*26) = 10 (720)(676) = 4867200 ways..........assuming numbers can't be repeated.

Ques doesn't say that the password should have first 2 as letters and last 3 as numbers, they can be anywhere thus I think we need to multiply by 5C3 = 10 also.


Great point!!!

I'd have said P(5,5)/(P(2,2)P(3,3)) though, what's your reasoning for C(5,3)? I mean we'd get the same number but obviously your method is better.
avatar
HongHu
Director
Director
Joined: 03 Jan 2005
Posts: 971
Own Kudos [?]: 769 [0]
Given Kudos: 0
Send PM
Re: A computer password consists of two letters, which are [#permalink] New post   09 Feb 2005, 12:30
Pick the positions for the numbers, and then put the letters into the remaining postions. I got you.

Or you can say C(5,2), same thing.

Good job baner!
User avatar
banerjeea_98
Director
Director
Joined: 18 Nov 2004
Posts: 679
Own Kudos [?]: 198 [0]
Given Kudos: 0
Send PM
Re: A computer password consists of two letters, which are [#permalink] New post   09 Feb 2005, 12:39
HongHu wrote:
Pick the positions for the numbers, and then put the letters into the remaining postions. I got you.

Or you can say C(5,2), same thing.

Good job baner!


Yep u got it, pick 3 positions or 2 positions, same ans. This is a combination, permutation problem.



Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Quantitative Questions Forum
Still interested in this question? Check out the "Best Topics" block above for a better discussion on this exact question, as well as several more related questions.
Thank you for understanding, and happy exploring!
GMAT Club Bot
gmatclubot
Re: A computer password consists of two letters, which are [#permalink]
09 Feb 2005, 12:39
Moderator:
yashikaaggarwal
Senior Moderator - Masters Forum
3137 posts

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