|
|
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
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
11 Sep 2021, 03:43
Kudos
Bookmarks
B
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
75%
(hard)
Question Stats:
58% (02:19) correct
42%
(02:22)
wrong
based on 423
sessions
History
Date
Time
Result
Not Attempted Yet
A unique code is assigned to all test takers of the GNAT exam on a specific day in a centre. On 12 Jan 2021, there were 32 test takers with the codes. The codes are either 2-letter codes or 3-letter codes in the alphabetical order. How many letters will the centre need at a minimum to give all the test takers a unique code?
A. 5
B. 6
C. 7
D. 8
E. 9
A. 5
B. 6
C. 7
D. 8
E. 9
12 Sep 2021, 03:37
Kudos
Bookmarks
Kushchokhani
Let the number of alphabets be n, and since we are looking at alphabetical order, each combination will just give one way.
So, we are looking at ways to choose 2 or 3 alphabets out of n.
\(nC2+nC3\geq 32\)
Use options to ease calculations.
1) 5:
\(5C2+5C3\geq 32………..10+10\geq 32\)…..NO
2) 6:
\(6C2+6C3\geq 32………..15+20\geq 32\)…..YES
B
General Discussion
rvgmat12
Joined: 19 Oct 2014
Last visit: 27 Mar 2026
Posts: 352
Own Kudos:
Given Kudos: 189
Location: United Arab Emirates
Schools: Wharton '23 Booth '23 INSEAD Jan'21 Intake
Products:
12 Sep 2021, 08:51
Kudos
Bookmarks
nC2+nC3 >= 32
5 - 10+10 = 20
6 works - 15+20 = 35 >= 32
B
5 - 10+10 = 20
6 works - 15+20 = 35 >= 32
B
