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.
Which of the following numbers is NOT the sum of three consecutive o
[#permalink]
20 Jul 2021, 04:39
20 Jul 2021, 04:39
Expert Reply
00:00
Question Stats:
85% (01:33) correct
14% (01:09) wrong based on 7 sessions
Hide Show timer Statistics
Which of the following numbers is NOT the sum of three consecutive odd integers?
(A) 15
(B) 75
(C) 123
(D) 297
(E) 313
Kudos for the right answer and explanation
Question part of the project GRE Quantitative Reasoning Daily Challenge - (2021) EDITION
GRE - Math Book
(A) 15
(B) 75
(C) 123
(D) 297
(E) 313
Kudos for the right answer and explanation
Question part of the project GRE Quantitative Reasoning Daily Challenge - (2021) EDITION
GRE - Math Book
Re: Which of the following numbers is NOT the sum of three consecutive o
[#permalink]
20 Jul 2021, 04:55
20 Jul 2021, 04:55
for consecutive odd integer let assume x-2,x,x+2
so sum is 3x,
so the answer should be the number that is not divisible by 3
Only option E satisfies i.e 313
so sum is 3x,
so the answer should be the number that is not divisible by 3
Only option E satisfies i.e 313
Moderator
Joined: 02 Jan 2020
Status:GRE Quant Tutor
Posts: 1111
Given Kudos: 9
Location: India
Concentration: General Management
Schools: XLRI Jamshedpur, India - Class of 2014
GMAT 1: 700 Q51 V31
GPA: 2.8
WE:Engineering (Computer Software)
Which of the following numbers is NOT the sum of three consecutive o
[#permalink]
20 Jul 2021, 05:25
20 Jul 2021, 05:25
1
Thee consecutive Odd Numbers can be taken as n-2, n, n+2
So, their sum becomes n-2 + n + n +2 = 3n
=> Sum of three consecutive odd numbers should be a multiple of 3
Divisibility rule of 3 is Sum of all the digits of the number should be divisible by 3
Let's check all the options choices now
(A) 15 -> Sum of digits = 1+5 = 6 => Divisible by 3 => POSSIBLE
(B) 75 -> Sum of digits = 7+5 = 12 => Divisible by 3 => POSSIBLE
(C) 123 -> Sum of digits = 1+2+3 = 6 => Divisible by 3 => POSSIBLE
(D) 297 -> Sum of digits = 2+9+7 = 18 => Divisible by 3 => POSSIBLE
(E) 313 -> Sum of digits = 3+1+3 = 7 => NOT Divisible by 3 => NOT POSSIBLE
So, Answer will be E
Hope it helps!
Watch the following video to learn the Basics of Divisibility Rules
So, their sum becomes n-2 + n + n +2 = 3n
=> Sum of three consecutive odd numbers should be a multiple of 3
Divisibility rule of 3 is Sum of all the digits of the number should be divisible by 3
Let's check all the options choices now
(A) 15 -> Sum of digits = 1+5 = 6 => Divisible by 3 => POSSIBLE
(B) 75 -> Sum of digits = 7+5 = 12 => Divisible by 3 => POSSIBLE
(C) 123 -> Sum of digits = 1+2+3 = 6 => Divisible by 3 => POSSIBLE
(D) 297 -> Sum of digits = 2+9+7 = 18 => Divisible by 3 => POSSIBLE
(E) 313 -> Sum of digits = 3+1+3 = 7 => NOT Divisible by 3 => NOT POSSIBLE
So, Answer will be E
Hope it helps!
Watch the following video to learn the Basics of Divisibility Rules
