Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 30 Aug 2015, 21:16

### 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 June
Open Detailed Calendar

# OG 12 Algebra First-degree equation Question 70

Author Message
TAGS:
Manager
Joined: 21 Jul 2010
Posts: 56
Followers: 1

Kudos [?]: 11 [0], given: 3

OG 12 Algebra First-degree equation Question 70 [#permalink]  22 Dec 2010, 16:28
00:00

Difficulty:

15% (low)

Question Stats:

71% (01:30) correct 29% (00:27) wrong based on 51 sessions
if $$y\frac{3x-5}{2}=y$$ and y is different from 0, then $$x=$$
A) $$\frac{2}{3}$$
B) $$\frac{5}{3}$$
C) $$\frac{7}{3}$$
D) 1
E) 4

Reasoning, see the spoiler part:

[Reveal] Spoiler:
I got it wrong because when I did the calculation I swapped y on the right hand side to the left hand side to get $$(3x-5)/2=0$$ and then obviously I got the answer B rather than the OA C. I understand the OA however I would like to ask my silly question, which is why can I not do the way I did it. Is it wrong? It must be but WHY?

Thank you for enlightening me. I searched for the topic in the forum and I could not find it. Apologise if it has been created in the past.
[Reveal] Spoiler: OA
Ms. Big Fat Panda
Status: Three Down.
Joined: 09 Jun 2010
Posts: 1923
Concentration: General Management, Nonprofit
Followers: 394

Kudos [?]: 1621 [0], given: 210

Re: OG 12 Algebra First-degree equation Question 70 [#permalink]  22 Dec 2010, 16:39
Expert's post
Burnkeal wrote:
if $$y\frac{3x-5}{2}=y$$ and y is different from 0, then $$x=$$
A) $$\frac{2}{3}$$
B) $$\frac{5}{3}$$
C) $$\frac{7}{3}$$
D) 1
E) 4

Reasoning, see the spoiler part:

[Reveal] Spoiler:
I got it wrong because when I did the calculation I swapped y on the right hand side to the left hand side to get $$(3x-5)/2=0$$ and then obviously I got the answer B rather than the OA C. I understand the OA however I would like to ask my silly question, which is why can I not do the way I did it. Is it wrong? It must be but WHY?

Thank you for enlightening me. I searched for the topic in the forum and I could not find it. Apologise if it has been created in the past.

$$y\frac{3x-5}{2}=y$$

$$y (\frac{3x-5}{2} -1) = 0$$, and hence $$\frac{3x-5}{2} = 1$$ and hence $$x = \frac{7}{3}$$

The mistake you made was equating it to zero. If you cancel y on both sides (which you can, since its not zero), the right hand side will be 1, not 0. Hope its clear.
Manager
Joined: 21 Jul 2010
Posts: 56
Followers: 1

Kudos [?]: 11 [0], given: 3

Re: OG 12 Algebra First-degree equation Question 70 [#permalink]  22 Dec 2010, 16:44
haha! I just got it. What a numb! Thanks for that. I just took Y to the other side rather than cancelling it out -____-
Ms. Big Fat Panda
Status: Three Down.
Joined: 09 Jun 2010
Posts: 1923
Concentration: General Management, Nonprofit
Followers: 394

Kudos [?]: 1621 [0], given: 210

Re: OG 12 Algebra First-degree equation Question 70 [#permalink]  22 Dec 2010, 16:55
Expert's post
Well, technically, so did I. You just equated the wrong thing to zero
Manager
Joined: 05 Oct 2011
Posts: 167
GMAT 1: 720 Q V
Followers: 9

Kudos [?]: 43 [0], given: 60

Re: OG 12 Algebra First-degree equation Question 70 [#permalink]  18 Nov 2011, 11:59
This Q shows how test makers create all other (wrong) answer choices. Each one is there to catch us for a particular miscalculation.
Re: OG 12 Algebra First-degree equation Question 70   [#permalink] 18 Nov 2011, 11:59
Similar topics Replies Last post
Similar
Topics:
1 Algebra: both sides of the equation 1 10 Jul 2011, 06:29
Algebra Question 3 02 Jul 2010, 22:38
OG 12 PS - Question 163 9 24 Apr 2010, 22:20
1 OG11/ Algebra 3 14 Apr 2010, 22:05
3 MGMAT Q' s Equation formation-algebra 8 18 Mar 2010, 05:14
Display posts from previous: Sort by