Last visit was: 14 Nov 2024, 06:16 It is currently 14 Nov 2024, 06:16

Close

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

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 GRE 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
Verbal Expert
Joined: 18 Apr 2015
Posts: 29958
Own Kudos [?]: 36219 [2]
Given Kudos: 25903
Send PM
Retired Moderator
Joined: 07 Jan 2018
Posts: 739
Own Kudos [?]: 1444 [0]
Given Kudos: 93
Send PM
avatar
Intern
Intern
Joined: 27 Jun 2019
Posts: 40
Own Kudos [?]: 17 [0]
Given Kudos: 0
Send PM
User avatar
Director
Director
Joined: 22 Jun 2019
Posts: 521
Own Kudos [?]: 709 [0]
Given Kudos: 161
Send PM
Re: The retirement plan for a company allows employees to invest [#permalink]
Carcass wrote:
The retirement plan for a company allows employees to invest in 10 different mutual funds. Six of the 10 funds grew by at least 10% over the last year. If Sam randomly selected 4 of the 10 funds, what is the probability that at least 3 of Sam’s 4 funds grew by at least 10% over the last year?

(A) \(\frac{6C_3}{10C_4}\)

(B) \(\frac{6C_3*4C_1}{10C_4}\)

(C) \(\frac{6C_3*4C_1+6C_4}{10P_4}\)

(D) \(\frac{6P_3*4P_1}{10C_4}\)

(E) \(\frac{6C_3*4C_1 + 6C_4}{10C_4}\)



There are 6 winning funds that grew more than 10%, and 4 losing funds that grew less than 10%.

The problem can be split into 3 sub-problems:

1) Sam has to choose 3 winning funds. This can be done in \(6C_3\) ways.

2) Sam has to choose 1 losing fund. This can be done in \(4C_1\) ways.

3) Sam has to choose all 4 funds to be winning funds. This can be done in \(6C_4\) ways.

This is how Sam chooses at least 3 winning funds. Hence, the total number of ways of choosing at least 3 winning funds is \(6C_3\)*\(4C_1\) + \(6C_4\)

If there were no restrictions (such as choosing at least 3 winning funds), Sam would have chosen funds in \(10C_4\) ways.

Hence, the probability that at least 3 of Sam’s 4 funds grew by at least 10% over the last year is \(\frac{6C_3*4C_1 + 6C_4}{10C_4}\)
User avatar
GRE Prep Club Legend
GRE Prep Club Legend
Joined: 07 Jan 2021
Posts: 5014
Own Kudos [?]: 74 [0]
Given Kudos: 0
Send PM
Re: The retirement plan for a company allows employees to invest [#permalink]
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.
Prep Club for GRE Bot
Re: The retirement plan for a company allows employees to invest [#permalink]
Moderators:
GRE Instructor
78 posts
GRE Forum Moderator
37 posts
Moderator
1111 posts
GRE Instructor
234 posts

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