Last visit was: 25 Apr 2024, 08:45 It is currently 25 Apr 2024, 08:45

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.
Close
Request Expert Reply
Confirm Cancel
SORT BY:
Kudos
Tags:
Show Tags
Hide Tags
e-GMAT Representative
Joined: 04 Jan 2015
Posts: 3726
Own Kudos [?]: 16836 [2]
Given Kudos: 165
Send PM
e-GMAT Representative
Joined: 04 Jan 2015
Posts: 3726
Own Kudos [?]: 16836 [1]
Given Kudos: 165
Send PM
Senior PS Moderator
Joined: 26 Feb 2016
Posts: 2873
Own Kudos [?]: 5205 [0]
Given Kudos: 47
Location: India
GPA: 3.12
Send PM
Senior Manager
Senior Manager
Joined: 27 Mar 2017
Posts: 274
Own Kudos [?]: 76 [0]
Given Kudos: 406
Location: Saudi Arabia
GMAT 1: 700 Q47 V39
GPA: 3.36
Send PM
Re: An unfortunate thief was caught while trying to decode the 3-digit num [#permalink]
EgmatQuantExpert wrote:

Solution



Given:
    • The thief was trying to decode a 3-digit numerical code of a lock
    • He was caught while making the second-last possible event

To find:
    • In total, how many attempts did the thief make

Approach and Working:
    • As it is a 3-digit numerical code, every place in the code can be filled by 10 possible digits
    • Therefore, total number of possible codes = 10 * 10 * 10 = 1000
However, among all the 1000 codes, only 1 is correct
    • Therefore, the maximum number of unsuccessful attempts = second-last possible unique attempts = 1000 – 1 = 999

Hence, the correct answer is option D.

Answer: D


Hi,

I have a questions regarding this. When we say 10x10x10 will this method count e.g a combination of 322 as one of two possible identical choices ? I mean will it consider the two 2s as different or as same ? My guess is that since this is a permutation based approach it will count the two 322s as different. Similarly the result should contain three combinations of 333s. Is this true ?

Will appreciate a response on this.
Target Test Prep Representative
Joined: 14 Oct 2015
Status:Founder & CEO
Affiliations: Target Test Prep
Posts: 18760
Own Kudos [?]: 22051 [0]
Given Kudos: 283
Location: United States (CA)
Send PM
An unfortunate thief was caught while trying to decode the 3-digit num [#permalink]
Expert Reply
EgmatQuantExpert wrote:
An unfortunate thief was caught while trying to decode the 3-digit numerical code of a lock. The Police caught him while he was making the second-last possible unique attempt. How many attempts did the thief make in total?

A. 5
B. 26
C. 719
D. 999
E. 1000



Solution:

The second-last attempt is the same thing as the next-to-last attempt. Since there are 10 x 10 x 10 = 1000 codes possible, including his second-last possible attempt, the thief has made a total of 999 attempts.

Answer: D
GMAT Club Bot
An unfortunate thief was caught while trying to decode the 3-digit num [#permalink]
Moderators:
Math Expert
92914 posts
Senior Moderator - Masters Forum
3137 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne