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.
a > 0 || (a + 2)(3a + 6)
[#permalink]
06 Apr 2018, 15:26
06 Apr 2018, 15:26
Expert Reply
00:00
Question Stats:
75% (01:08) correct
24% (00:46) wrong based on 37 sessions
Hide Show timer Statistics
a > 0
A. Quantity A is greater.
B. Quantity B is greater.
C. The two quantities are equal.
D. The relationship cannot be determined from the information given.
Quantity A |
Quantity B |
\((a + 2)(3a + 6)\) |
\((3a + 2)(a + 6)\) |
A. Quantity A is greater.
B. Quantity B is greater.
C. The two quantities are equal.
D. The relationship cannot be determined from the information given.
Drill 1
Question: 2
Page: 507
Question: 2
Page: 507
Re: a > 0 || (a + 2)(3a + 6)
[#permalink]
15 Apr 2018, 05:24
15 Apr 2018, 05:24
Expert Reply
Explanation
For Quantity A, you get \(3a^2 + 6a + 6a + 12\), or \(3a^2 + 12a + 12\).
For Quantity B, you get \(3a^2 + 18a + 2a + 12\), or \(3a^2 + 20a + 12\).
Remember to compare, not calculate.
Notice that the only difference between the quantities is that between 20a and 12a. Because a is positive, 20a must be greater than 12a, thus, Quantity B will always be greater.
For Quantity A, you get \(3a^2 + 6a + 6a + 12\), or \(3a^2 + 12a + 12\).
For Quantity B, you get \(3a^2 + 18a + 2a + 12\), or \(3a^2 + 20a + 12\).
Remember to compare, not calculate.
Notice that the only difference between the quantities is that between 20a and 12a. Because a is positive, 20a must be greater than 12a, thus, Quantity B will always be greater.
Retired Moderator
Joined: 10 Apr 2015
Posts: 6218
Given Kudos: 136
Re: a > 0 || (a + 2)(3a + 6)
[#permalink]
23 Mar 2021, 05:04
23 Mar 2021, 05:04
sandy wrote:
a > 0
Quantity A |
Quantity B |
\((a + 2 |
3a + 6)\))(\((3a + 2)(a + 6)\) |
We can solve this question using matching operations (my favorite Quantitative Comparison strategy)
Given:
Quantity A: \((a + 2)(3a + 6)\)
Quantity B: \((3a + 2)(a + 6)\)
Expand and simplify both quantities to get:
Quantity A: \(3a^2 + 12a + 12\)
Quantity B: \(3a^2 + 20a + 12\)
Subtract \(3a^2\) from both quantities to get:
Quantity A: \(12a + 12\)
Quantity B: \(20a + 12\)
Subtract \(12\) from both quantities to get:
Quantity A: \(12a\)
Quantity B: \(20a\)
Subtract \(12a\) from both quantities to get:
Quantity A: \(0\)
Quantity B: \(8a\)
At this point, we can see that:
If a = 0, the quantities are equal
If a < 0, Quantity A is greater
If a > 0, Quantity B is greater
Answer: D
RELATED VIDEO
