Last visit was: 24 Nov 2024, 13:09 It is currently 24 Nov 2024, 13:09

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
Senior Manager
Senior Manager
Joined: 17 Aug 2019
Posts: 381
Own Kudos [?]: 200 [6]
Given Kudos: 96
Send PM
Senior Manager
Senior Manager
Joined: 17 Aug 2019
Posts: 381
Own Kudos [?]: 200 [0]
Given Kudos: 96
Send PM
Verbal Expert
Joined: 18 Apr 2015
Posts: 30017
Own Kudos [?]: 36379 [0]
Given Kudos: 25928
Send PM
avatar
Active Member
Active Member
Joined: 27 Aug 2019
Posts: 59
Own Kudos [?]: 74 [0]
Given Kudos: 0
Send PM
Re: S is the set of all [#permalink]
The largest integer for which (n-1)/n is less than 0.8 is 4 (3/4 = 0.75)

The smallest integer that respect the condition (n-1)/n > 0 is instead 2 (1/2 = 0.5)

Hence, we have to multiply 3/4 * 2/3 * 1/2 = 0.25 > 0.1

The answer is A.
Retired Moderator
Joined: 16 Apr 2020
Status:Founder & Quant Trainer
Affiliations: Prepster Education
Posts: 1546
Own Kudos [?]: 3224 [1]
Given Kudos: 172
Location: India
WE:Education (Education)
Send PM
S is the set of all [#permalink]
1
Asmakan wrote:
MY Question : when I multiply .1x.2x.3x.4x.5 .. 0.7
The answer is less than 0.1. So, why the answer is A and not the way I did it ?
Please I need someone to analyze to to answer the question above only



S will have fractions less that 0.8, does not mean all values less than 0.8!
Why just 0.1 x 0.2 x ....... x 0.7, we could also have 0.01 x 0.02 x 0.03 x ..... x 0.77 x 0.78 x 0.79 ???

These fractions are less than 0.8 but n must be an integers too!
So, S can only have {1/2, 2/3, 3/4} ........... [using (n-1) / n ]

Col. A = 1/2 x 2/3 x 3/4 = 1/4 = 0.25
Col. B = 0.1

Hence, option A
Intern
Intern
Joined: 17 May 2019
Posts: 15
Own Kudos [?]: 13 [0]
Given Kudos: 62
Location: India
Concentration: Finance, Leadership
GPA: 3.7
WE:General Management (Health Care)
Send PM
Re: S is the set of all [#permalink]
KarunMendiratta wrote:
Asmakan wrote:
MY Question : when I multiply .1x.2x.3x.4x.5 .. 0.7
The answer is less than 0.1. So, why the answer is A and not the way I did it ?
Please I need someone to analyze to to answer the question above only



S will have fractions less that 0.8, does not mean all values less than 0.8!
Why just 0.1 x 0.2 x ....... x 0.7, we could also have 0.01 x 0.02 x 0.03 x ..... x 0.77 x 0.78 x 0.79 ???

These fractions are less than 0.8 but n must be an integers too!
So, S can only have {1/2, 2/3, 3/4} ........... [using (n-1) / n ]

Col. A = 1/2 x 2/3 x 3/4 = 1/4 = 0.25
Col. B = 0.1

Hence, option A


Why not the answer is D?

If we take n=1 , it gives us a fraction as 0/1 . so the product of all the fractions wouldn't be zero? isn't 0/1 a positive fraction?
Retired Moderator
Joined: 16 Apr 2020
Status:Founder & Quant Trainer
Affiliations: Prepster Education
Posts: 1546
Own Kudos [?]: 3224 [0]
Given Kudos: 172
Location: India
WE:Education (Education)
Send PM
Re: S is the set of all [#permalink]
hkmhj wrote:
KarunMendiratta wrote:
Asmakan wrote:
MY Question : when I multiply .1x.2x.3x.4x.5 .. 0.7
The answer is less than 0.1. So, why the answer is A and not the way I did it ?
Please I need someone to analyze to to answer the question above only



S will have fractions less that 0.8, does not mean all values less than 0.8!
Why just 0.1 x 0.2 x ....... x 0.7, we could also have 0.01 x 0.02 x 0.03 x ..... x 0.77 x 0.78 x 0.79 ???

These fractions are less than 0.8 but n must be an integers too!
So, S can only have {1/2, 2/3, 3/4} ........... [using (n-1) / n ]

Col. A = 1/2 x 2/3 x 3/4 = 1/4 = 0.25
Col. B = 0.1

Hence, option A


Why not the answer is D?

If we take n=1 , it gives us a fraction as 0/1 . so the product of all the fractions wouldn't be zero? isn't 0/1 a positive fraction?


\(\frac{0}{1}\) will yield 0 which is a neutral integer.
0 is neither positive nor negative.
Manager
Manager
Joined: 03 Nov 2021
Posts: 92
Own Kudos [?]: 101 [1]
Given Kudos: 17
Send PM
S is the set of all [#permalink]
1
\(\frac{n-1}{n} < 0.8\)

\(1 - \frac{1}{n} < 1 - 0.2\)

\(-\frac{1}{n} < -0.2\)

\(\frac{-1}{n} < \frac{-1}{5}\)

\(\frac{1}{n} > \frac{1}{5}\)

\(n < 5\)

Since set S has positive fractions, by a little math you can tell that \(n>1\), \(\frac{1 - 1}{1} = 0\)

Therefore, \(1 < n < 5\)

Product of all elements of S = \(\frac{2-1}{2}*\frac{3-1}{3}*\frac{4-1}{4} = \frac{1}{2}*\frac{2}{3}*\frac{3}{4} = \frac{1}{4}\) = 0.25 > 0.1

Hence answer is A
User avatar
GRE Prep Club Legend
GRE Prep Club Legend
Joined: 07 Jan 2021
Posts: 5046
Own Kudos [?]: 74 [0]
Given Kudos: 0
Send PM
Re: S is the set of all [#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: S is the set of all [#permalink]
Moderators:
GRE Instructor
84 posts
GRE Forum Moderator
37 posts
Moderator
1111 posts
GRE Instructor
234 posts

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