GRE Prep 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.
A certain band will perform 15 different songs in random ord
[#permalink]
28 Dec 2019, 13:16
28 Dec 2019, 13:16
1
Expert Reply
00:00
Question Stats:
100% (01:17) correct
0% (00:00) wrong based on 22 sessions
Hide Show timer Statistics
A certain band will perform 15 different songs in random order, and no song will be performed twice. If 9 of the songs are new, what is the probability that the first 2 songs that the band performs will both be new?
Give your answer as a fraction.
Give your answer as a fraction.
Show: :: OA
\(\frac{12}{35}\)
Re: A certain band will perform 15 different songs in random ord
[#permalink]
29 Dec 2019, 01:00
29 Dec 2019, 01:00
1
We have to select two songs such that both of them are new.
Total new songs available = 9
Probability = \(\frac{9C2}{15C2}\) = \(\frac{9*8}{15*14}\)
Probability = \(\frac{12}{35}\)
Total new songs available = 9
Probability = \(\frac{9C2}{15C2}\) = \(\frac{9*8}{15*14}\)
Probability = \(\frac{12}{35}\)
Carcass wrote:
A certain band will perform 15 different songs in random order, and no song will be performed twice. If 9 of the songs are new, what is the probability that the first 2 songs that the band performs will both be new?
Give your answer as a fraction.
Give your answer as a fraction.
Show: :: OA
\(\frac{12}{35}\)
Re: A certain band will perform 15 different songs in random ord
[#permalink]
09 Jan 2020, 01:22
09 Jan 2020, 01:22
1
Carcass wrote:
A certain band will perform 15 different songs in random order, and no song will be performed twice. If 9 of the songs are new, what is the probability that the first 2 songs that the band performs will both be new?
Give your answer as a fraction.
Give your answer as a fraction.
Show: :: OA
\(\frac{12}{35}\)
First and foremost the question is about arrangement and not selection
The Random experiment is about arranging 15 distinct songs which is 15!
The event is about arranging 2 new songs at the start (9P2) and then the remaining 13 songs (13!)
[9P2 * 13!][/15!]
= 12/35
