GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 16 Feb 2019, 23:51

### GMAT 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

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

## Events & Promotions

###### Events & Promotions in February
PrevNext
SuMoTuWeThFrSa
272829303112
3456789
10111213141516
17181920212223
242526272812
Open Detailed Calendar
• ### Free GMAT Algebra Webinar

February 17, 2019

February 17, 2019

07:00 AM PST

09:00 AM PST

Attend this Free Algebra Webinar and learn how to master Inequalities and Absolute Value problems on GMAT.
• ### Free GMAT Strategy Webinar

February 16, 2019

February 16, 2019

07:00 AM PST

09:00 AM PST

Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT.

# If x^2 = 2y^3 and 2y = 4, what is the value of x^2 + y?

Author Message
TAGS:

### Hide Tags

Manager
Joined: 22 Mar 2012
Posts: 85
Location: United States (NY)
Concentration: General Management, Marketing
GPA: 3.1
WE: Accounting (Other)
If x^2 = 2y^3 and 2y = 4, what is the value of x^2 + y?  [#permalink]

### Show Tags

Updated on: 24 Aug 2012, 20:39
3
00:00

Difficulty:

5% (low)

Question Stats:

92% (00:56) correct 8% (01:48) wrong based on 87 sessions

### HideShow timer Statistics

If x^2 = 2y^3 and 2y = 4, what is the value of x^2 + y?

A. -14
B. -2
C. 3
D. 6
E. 18

I understand how they came to the answer. But I'm confused as to why I can't replace 2y in the first equation with 4 to get x^2 = 64. That would give the equation x^2 + y, value of 66. Please tell me what am I missing? Attaching the screenshot of the question and answer. This is from the GMAC software.

Attachments

Gmac Problem.png [ 798.6 KiB | Viewed 5044 times ]

Originally posted by KAS1 on 24 Aug 2012, 12:36.
Last edited by Bunuel on 24 Aug 2012, 20:39, edited 1 time in total.
Edited the question.
Director
Joined: 22 Mar 2011
Posts: 599
WE: Science (Education)

### Show Tags

24 Aug 2012, 12:49
KAS1 wrote:
If x^2 = 2y^3 and 2y = 4, what is the value of x^2 + y?

A. -14
B. -2
C. 3
D. 6
E. 18

I understand how they came to the answer. But I'm confused as to why I can't replace 2y in the first equation with 4 to get x^2 = 64. That would give the equation x^2 + y, value of 66. Please tell me what am I missing? Attaching the screenshot of the question and answer. This is from the GMAC software.

In the equation it is $$2y^3$$ and not $$(2y)^3.$$ Therefore $$2y^3=2*2^3=16,$$ because from $$2y=4,$$we obtain $$y=2.$$
_________________

PhD in Applied Mathematics
Love GMAT Quant questions and running.

Manager
Joined: 22 Mar 2012
Posts: 85
Location: United States (NY)
Concentration: General Management, Marketing
GPA: 3.1
WE: Accounting (Other)

### Show Tags

24 Aug 2012, 18:04
Wow!
Thanks so much. I have to pay attention to these little things on the exam.
Intern
Joined: 13 Dec 2018
Posts: 1
Re: If x^2 = 2y^3 and 2y = 4, what is the value of x^2 + y?  [#permalink]

### Show Tags

12 Feb 2019, 09:05
if x^2=2y^3 and 2y=4
X^2= 2(2)^3 [y=2]
X^2=2*8
X^2=16
X=4
Equation:- x^2+y
=(4)^2+2
=16+2
=18

Posted from my mobile device
Re: If x^2 = 2y^3 and 2y = 4, what is the value of x^2 + y?   [#permalink] 12 Feb 2019, 09:05
Display posts from previous: Sort by