BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Permuations

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 268
Joined: Mon Mar 15, 2010 12:10 am
Thanked: 13 times

Permuations

by shekhar.kataria » Wed Mar 28, 2012 4:50 am
A password contains at least 8 distinct digits. It takes 12 seconds to try one combination, what is the minimum amount of time required to guarantee access to the database?

[spoiler]Can the first digit of 8 digit password be zero....? Please solve the Question for me also.[/spoiler]
Restlessness and discontent are the first necessities of progress.--Thomas A. Edison

If you find this post helpful, let me know by clicking thanks above :-)
Top
Source: — Problem Solving |
User avatar
Legendary Member
Posts: 1239
Joined: Tue Apr 26, 2011 6:25 am
Thanked: 233 times
Followed by:26 members
GMAT Score:680

by sam2304 » Wed Mar 28, 2012 5:37 am
Yes. It is a password and not a value.

Since the password can have 8 digits and we have total of 10 digits we have to calculate for every combination. So codes with 0-7 as digits = 10P8
codes with 0-8 as digits = 10P9
codes with 0-9 as digits = 10P10

(10P8 + 10P9 + 10P10)*12
Getting defeated is just a temporary notion, giving it up is what makes it permanent.
https://gmatandbeyond.blogspot.in/
Top
User avatar
Legendary Member
Posts: 626
Joined: Fri Dec 23, 2011 2:50 am
Location: Ahmedabad
Thanked: 31 times
Followed by:10 members

by ronnie1985 » Wed Mar 28, 2012 7:42 am
At least 8 digits. Assuming that the password is of minimum digits only, the time required = 10P8*12
Similarly for 9 and 10 digits 10P9*12 and 10P10*12.

Since minimum assured time is asked I think the answer is 10P8*12 seconds.
Follow your passion, Success as perceived by others shall follow you
Top
User avatar
Legendary Member
Posts: 934
Joined: Tue Nov 09, 2010 5:16 am
Location: AAMCHI MUMBAI LOCAL
Thanked: 63 times
Followed by:14 members

by [email protected] » Sat Mar 31, 2012 2:26 am
Yes Ronnie said is perfectly right... It shall be 10P8 X 12/60

This will give you the total time taken for the gurrantee of accessing the database.

Also this is a good question as to Can a password start from 0 or no.

I think if not then the question should explicitly state that. Because if it does not then the answers will be wrong..;

Also if the question does not state it explicitely then, the options would be better.

It would be simple to figure out between the options...

Hope this helps...
IT IS TIME TO BEAT THE GMAT

LEARNING, APPLICATION AND TIMING IS THE FACT OF GMAT AND LIFE AS WELL... KEEP PLAYING!!!

Whenever you feel that my post really helped you to learn something new, please press on the 'THANK' button.
Top

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 3835
Joined: Fri Apr 02, 2010 10:00 pm
Location: Milpitas, CA
Thanked: 1854 times
Followed by:523 members
GMAT Score:770

by Anurag@Gurome » Sun Apr 01, 2012 9:06 pm
shekhar.kataria wrote:A password contains at least 8 distinct digits. It takes 12 seconds to try one combination, what is the minimum amount of time required to guarantee access to the database?

[spoiler]Can the first digit of 8 digit password be zero....? Please solve the Question for me also.[/spoiler]
Total number of passwords possible = 10P8
12 seconds = 12/60 = 1/5 minute

Therefore, minimum amount of time required to guarantee access to the database = [spoiler]10P8 * 1/5[/spoiler] minute
Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)

Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/
Top
Post new topic Post Reply
• Page 1 of 1