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 + b = 20, then (a + b/2) + (b + a/2) =
[#permalink]
06 Feb 2018, 21:05
06 Feb 2018, 21:05
1
1
Bookmarks
00:00
Question Stats:
67% (01:03) correct
32% (00:35) wrong based on 28 sessions
Hide Show timer Statistics
If a + b = 20, then (a + b/2) + (b + a/2) =
A) 10
B) 20
C) 30
D) 40
E) 50
A) 10
B) 20
C) 30
D) 40
E) 50
Sherpa Prep Representative
Joined: 15 Jan 2018
Posts: 147
Given Kudos: 0
Re: If a + b = 20, then (a + b/2) + (b + a/2) =
[#permalink]
06 Feb 2018, 22:16
06 Feb 2018, 22:16
1
Expert Reply
Notice that if you just add the terms you get a simple question:
(a + b/2) + (b + a/2) = 1.5a + 1.5b = ?
Then you can factor:
1.5a + 1.5b = 1.5(a + b)
and since we know a + b = 20, then 1.5(a + b) = 30
(a + b/2) + (b + a/2) = 1.5a + 1.5b = ?
Then you can factor:
1.5a + 1.5b = 1.5(a + b)
and since we know a + b = 20, then 1.5(a + b) = 30
Retired Moderator
Joined: 10 Apr 2015
Posts: 6218
Given Kudos: 136
Re: If a + b = 20, then (a + b/2) + (b + a/2) =
[#permalink]
17 Feb 2018, 11:38
17 Feb 2018, 11:38
1
amorphous wrote:
If a + b = 20, then (a + b/2) + (b + a/2) =
A) 10
B) 20
C) 30
D) 40
E) 50
A) 10
B) 20
C) 30
D) 40
E) 50
Here's another approach:
GOAL: find the value of (a + b/2) + (b + a/2)
GIVEN: a + b = 20
Let's take some values of a and b that satisfy the equation a+b = 20, and plug them into our goal expression...
Well, a = 20 and b = 0 satisfy the equation a + b = 20
Now take (a + b/2) + (b + a/2), and replace a and b with 20 and b = 0
We get: (a + b/2) + (b + a/2) = (20 + 0/2) + (0 + 20/2)
= (20 + 0) + (0 + 10)
= 20 + 10
= 30
Answer: C
Cheers,
Brent
