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.
Kris and David work with n other workers. Two of the workers are to be
[#permalink]
26 Dec 2023, 04:43
26 Dec 2023, 04:43
Expert Reply
00:00
Question Stats:
40% (02:26) correct
60% (01:56) wrong based on 25 sessions
Hide Show timer Statistics
Kris and David work with n other workers. Two of the workers are to be chosen to work on a new project. What is the expression that gives the probability that both Kris and David will be chosen?
Indicate all possible expressions.
A. \(\dfrac{1}{n^2}\)
B. \(\dfrac{2}{(n+1)(n+2)}\)
C. \(\dfrac{1}{n(n+1)}\)
D. \(\dfrac{2}{n(n+3)+2}\)
E. \(\dfrac{1}{n^2+n}\)
Indicate all possible expressions.
A. \(\dfrac{1}{n^2}\)
B. \(\dfrac{2}{(n+1)(n+2)}\)
C. \(\dfrac{1}{n(n+1)}\)
D. \(\dfrac{2}{n(n+3)+2}\)
E. \(\dfrac{1}{n^2+n}\)
Part of the project: The Butler-GRE Daily New Quant and Verbal Questions to Practice (2023) - Gain 20 Kudos & Get FREE Access to GRE Prep Club TESTS
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Free Materials for the GRE General Exam - Where to get it!!
GRE Geometry Formulas
GRE - Math Book
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Free Materials for the GRE General Exam - Where to get it!!
GRE Geometry Formulas
GRE - Math Book
Manager
Joined: 11 Nov 2023
Posts: 228
Given Kudos: 78
WE:Business Development (Advertising and PR)
Kris and David work with n other workers. Two of the workers are to be
[#permalink]
09 Jan 2024, 20:11
09 Jan 2024, 20:11
2
Kris and David work with n other workers. Two of the workers are to be chosen to work on a new project. What is the expression that gives the probability that both Kris and David will be chosen?
The total number of workers, including Kris and David, is \(2+n\).
The probability that either Kris OR David gets chosen the first pick is \(\frac{2}{2+n}\). Now we're left with \(1+n\) total workers, and only one of Kris or David left in the pool.
The probability that the remaining of Kris or David gets chosen the second pick is \(\frac{1}{1+n}\).
Since we're picking without replacement, the probability that both happens is \(\frac{2}{2+n}*\frac{1}{1+n} = \frac{2}{(n+1)(n+2)} = \frac{2}{n(n+3)+2}\)
The total number of workers, including Kris and David, is \(2+n\).
The probability that either Kris OR David gets chosen the first pick is \(\frac{2}{2+n}\). Now we're left with \(1+n\) total workers, and only one of Kris or David left in the pool.
The probability that the remaining of Kris or David gets chosen the second pick is \(\frac{1}{1+n}\).
Since we're picking without replacement, the probability that both happens is \(\frac{2}{2+n}*\frac{1}{1+n} = \frac{2}{(n+1)(n+2)} = \frac{2}{n(n+3)+2}\)
Re: Kris and David work with n other workers. Two of the workers are to be
[#permalink]
04 Jul 2026, 11:38
04 Jul 2026, 11:38
Hello from the GRE Prep Club BumpBot!
Thanks to another GRE Prep Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).
Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
Thanks to another GRE Prep Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).
Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
