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.
If the sum of the first n positive integers is S, what is the sum of t
[#permalink]
10 Jun 2022, 03:00
10 Jun 2022, 03:00
1
Expert Reply
2
Bookmarks
00:00
Question Stats:
49% (01:26) correct
49% (01:58) wrong based on 14 sessions
Hide Show timer Statistics
If the sum of the first n positive integers is S, what is the sum of the first n positive even integers, in terms of S ?
(A) S/2
(B) S
(C) 2S
(D) 2S + 2
(E) 4S
(A) S/2
(B) S
(C) 2S
(D) 2S + 2
(E) 4S
Part of the project: GRE QCQ & PS 3 Questions Every One DAILY Challenge - (2022)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
GRE Math Essentials for a TOP Quant Score - Q170!!! (2021)
GRE Geometry Formulas for a Q170
GRE - Math Book
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
GRE Math Essentials for a TOP Quant Score - Q170!!! (2021)
GRE Geometry Formulas for a Q170
GRE - Math Book
Retired Moderator
Joined: 10 Apr 2015
Posts: 6218
Given Kudos: 136
Re: If the sum of the first n positive integers is S, what is the sum of t
[#permalink]
10 Jun 2022, 05:28
10 Jun 2022, 05:28
1
Carcass wrote:
If the sum of the first n positive integers is S, what is the sum of the first n positive even integers, in terms of S ?
(A) S/2
(B) S
(C) 2S
(D) 2S + 2
(E) 4S
(A) S/2
(B) S
(C) 2S
(D) 2S + 2
(E) 4S
Given: The sum of the first n positive integers is S
So, we can write: S = 1 + 2 + 3 + 4 + . . . + n
Question: What is the sum of the first n positive even integers, in terms of S ?
Let E = the sum of the first n positive even integers
So, we can write: E = 2 + 4 + 6 + 8 + . . . + 2n
Factor out 2 to get: E = 2(1 + 2 + 3 + 4 + . . . + n)
Since S = 1 + 2 + 3 + 4 + . . . + n, we can substitute to get: E = 2(S)
Answer: C
Re: If the sum of the first n positive integers is S, what is the sum of t
[#permalink]
11 Jun 2022, 00:04
11 Jun 2022, 00:04
1
If we assume that S is any set of consecutive positive integers, then naturally, multiplying the set by 2 will give us a set of all that positive integers.
S = {1, 2, 3}
2S= {2, 4, 6}
One may experiment with other choices on a small set-frame.
The answer is (C)
S = {1, 2, 3}
2S= {2, 4, 6}
One may experiment with other choices on a small set-frame.
The answer is (C)
