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 a − c = 17, b − a = 12 and 2a + b + 3c = 7, then what is the value
[#permalink]
17 May 2021, 15:14
17 May 2021, 15:14
Expert Reply
5
Bookmarks
00:00
Question Stats:
94% (01:47) correct
5% (03:11) wrong based on 17 sessions
Hide Show timer Statistics
If a − c = 17, b − a = 12 and 2a + b + 3c = 7, then what is the value of a + b + c ?
A) 2
B) 6
C) 9
D) 12
E) 18
A) 2
B) 6
C) 9
D) 12
E) 18
Moderator
Joined: 02 Jan 2020
Status:GRE Quant Tutor
Posts: 1131
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)
If a c = 17, b a = 12 and 2a + b + 3c = 7, then what is the value
[#permalink]
18 May 2021, 07:53
18 May 2021, 07:53
2
1
Bookmarks
Usually in these kind of questions where you have a lot of equations then you just need to add all the equations to get the result
a − c = 17
b − a = 12
2a + b + 3c = 7
Adding all three of them we get
a − c + b − a + 2a + b + 3c = 17 + 12+ 7 = 36
=> 2a + 2b + 2c = 36
=> 2(a+b+c) = 36
=> a+b+c = 36/2 = 18
So, Answer will be E.
Hope it helps!
a − c = 17
b − a = 12
2a + b + 3c = 7
Adding all three of them we get
a − c + b − a + 2a + b + 3c = 17 + 12+ 7 = 36
=> 2a + 2b + 2c = 36
=> 2(a+b+c) = 36
=> a+b+c = 36/2 = 18
So, Answer will be E.
Hope it helps!
Retired Moderator
Joined: 10 Apr 2015
Posts: 6218
Given Kudos: 136
Re: If a − c = 17, b − a = 12 and 2a + b + 3c = 7, then what is the value
[#permalink]
12 Nov 2021, 11:04
12 Nov 2021, 11:04
Carcass wrote:
If a − c = 17, b − a = 12 and 2a + b + 3c = 7, then what is the value of a + b + c ?
A) 2
B) 6
C) 9
D) 12
E) 18
A) 2
B) 6
C) 9
D) 12
E) 18
Take the 3 equations and add them to get: (a − c) + (b − a) + (2a + b + 3c) = 17 +12 + 7
Simplify: 2a +2b + 2c = 36
Divide both sides by 2 to get: a + b + c = 18
Answer: E
