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If a + b = 20, then (a + b/2) + (b + a/2) =
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06 Feb 2018, 21:05
06 Feb 2018, 21:05
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Question Stats:
65% (00:59) correct
35% (00:34) wrong based on 20 sessions
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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) =
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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
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Re: If a + b = 20, then (a + b/2) + (b + a/2) =
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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
