May 25 07:00 AM PDT  09:00 AM PDT Attend this webinar and master GMAT SC in 10 days by learning how meaning and logic can help you tackle 700+ level SC questions with ease. May 27 01:00 AM PDT  11:59 PM PDT All GMAT Club Tests are free and open on May 27th for Memorial Day! May 27 10:00 PM PDT  11:00 PM PDT Special savings are here for Magoosh GMAT Prep! Even better  save 20% on the plan of your choice, now through midnight on Tuesday, 5/27 May 30 10:00 PM PDT  11:00 PM PDT Application deadlines are just around the corner, so now’s the time to start studying for the GMAT! Start today and save 25% on your GMAT prep. Valid until May 30th. Jun 01 07:00 AM PDT  09:00 AM PDT Learn reading strategies that can help even nonvoracious reader to master GMAT RC
Author 
Message 
TAGS:

Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 55272

A certain college party is attended by both male and female students.
[#permalink]
Show Tags
08 May 2015, 06:04
Question Stats:
85% (01:31) correct 15% (02:15) wrong based on 185 sessions
HideShow timer Statistics
A certain college party is attended by both male and female students. The ratio of male to female students is 3 to 5. If 5 of the male students were to leave the party, the ratio would change to 1 to 2. How many total students are at the party? (A) 24 (B) 30 (C) 48 (D) 64 (E) 80 Kudos for a correct solution.
Official Answer and Stats are available only to registered users. Register/ Login.
_________________




Manager
Status: Birds fly because they have wings, not because they have sky.
Joined: 21 Sep 2014
Posts: 210
Location: Singapore
Concentration: Strategy, Technology
GPA: 3.65
WE: Information Technology (Consulting)

Re: A certain college party is attended by both male and female students.
[#permalink]
Show Tags
08 May 2015, 23:17
Bunuel wrote: A certain college party is attended by both male and female students. The ratio of male to female students is 3 to 5. If 5 of the male students were to leave the party, the ratio would change to 1 to 2. How many total students are at the party?
(A) 24 (B) 30 (C) 48 (D) 64 (E) 80
Kudos for a correct solution. Correct answer to this question would be divisible by \(8 (3+5)\) and correct answer subtracted by \(5\) would be divisible by \(3\). Now lets put answer choices to solve the question: (A) 24 => Divisible by \(8\) but \(245=19\) is not divisible by \(3\). Incorrect (B) 30 => No divisible by \(8\). Incorrect (C) 48 => Divisible by \(8\) but \(485=43\) is not divisible by \(3\). Incorrect (D) 64 => Divisible by \(8\) but \(645=59\) is not divisible by \(3\). Incorrect (E) 80 => Divisible by \(8\) and \(805=75\) is divisible by \(3\). We have a winner. E is the correct answer.
_________________
Regards, J  Consider Kudos if I helped in some way!!!
Perseverance is the hard work you do after you get tired of doing the hard work you already did.




Manager
Joined: 05 Feb 2015
Posts: 51
Concentration: Finance, Entrepreneurship
WE: Information Technology (Health Care)

A certain college party is attended by both male and female students.
[#permalink]
Show Tags
09 May 2015, 01:54
M/F = 3/5 5M = 3F1 Also, (M5)/F = 1/2 2M10 = F Multiply by 3 both sides 3F=6M302 from 1 and 2 M=30 F=50 Total=80 E is the answer



Director
Joined: 21 May 2013
Posts: 656

Re: A certain college party is attended by both male and female students.
[#permalink]
Show Tags
09 May 2015, 07:41
Bunuel wrote: A certain college party is attended by both male and female students. The ratio of male to female students is 3 to 5. If 5 of the male students were to leave the party, the ratio would change to 1 to 2. How many total students are at the party?
(A) 24 (B) 30 (C) 48 (D) 64 (E) 80
Kudos for a correct solution. Ratio of males:females=3:5 or 3x:5x Now, (3x5)/5x=1:2 6x10=5x x=10 3x=30 5x=50 Total No of males=30 and Total no of females=50 Total no of students=80 Answer E



Intern
Joined: 19 Jan 2014
Posts: 20
Concentration: Marketing, Economics
GPA: 3.81

Re: A certain college party is attended by both male and female students.
[#permalink]
Show Tags
09 May 2015, 18:47
\(\frac{M}{F}\) =\(\frac{3}{5}\) This means, 5M=3F Now after 5 male leave the party, \(\frac{(M5)}{F}\) = \(\frac{1}{2}\) Substitute F= \(\frac{5M}{3}\) \(\frac{(M5)}{(5M/3)}\)= \(\frac{1}{2}\) 2(3M 15) = 5M M= 30 \(\frac{3}{8}\)* Total = 30 Total = 80 students



Manager
Joined: 09 Jan 2013
Posts: 69
Concentration: Entrepreneurship, Sustainability
GMAT 1: 650 Q45 V34 GMAT 2: 740 Q51 V39
GPA: 3.76
WE: Other (Pharmaceuticals and Biotech)

Re: A certain college party is attended by both male and female students.
[#permalink]
Show Tags
09 May 2015, 02:52
m/f = 3/5 Assume constant = x m=3x, f=5x
Now, 3x5/5x =1/2 => 6x10 = 5x => x=10 total students = 8x = 80
Answer E



Math Expert
Joined: 02 Sep 2009
Posts: 55272

Re: A certain college party is attended by both male and female students.
[#permalink]
Show Tags
11 May 2015, 06:53
Bunuel wrote: A certain college party is attended by both male and female students. The ratio of male to female students is 3 to 5. If 5 of the male students were to leave the party, the ratio would change to 1 to 2. How many total students are at the party?
(A) 24 (B) 30 (C) 48 (D) 64 (E) 80
Kudos for a correct solution. MANHATTAN GMAT OFFICIAL SOLUTION:Of course, we could set up equations for the unknowns in the problem and solve them algebraically. However, it may be easier just to test the answer choices. Give this approach a try: (A) 24 students implies 9 male and 15 female students. If 5 male students left the party, the remaining ratio would be 4/14 = 2/7. INCORRECT. (B) 30 students implies 11.25 male and 18.75 female students. These numbers must be integers. INCORRECT. (C) 48 students implies 18 male and 30 female students. If 5 male students left the party, the remaining ratio would be 13/30. INCORRECT. (D) 64 students implies 24 male and 40 female students. If 5 male students left the party, the remaining ratio would be 19/40. INCORRECT. (E) 80 students implies 30 male and 50 female students. If 5 male students left the party, the remaining ratio would be 25/50 = 1/2. CORRECT. We proved that the correct answer must be (E) without doing any algebra at all. A nice thing about Testing Answer Choices is that it doesn't require any fundamental knowledge or theory. You don't need to know a special formula. Instead, it forces you to concentrate on the available answer options. It also steadily reduces your uncertainty, since you eliminate wrong answer choices one by one. A question might contain a phrase such as “Which of the following…” This is a great time to test choices
_________________



Director
Joined: 26 Oct 2016
Posts: 633
Location: United States
Concentration: Marketing, International Business
GPA: 4
WE: Education (Education)

Re: A certain college party is attended by both male and female students.
[#permalink]
Show Tags
20 Feb 2017, 09:33
Bunuel wrote: Bunuel wrote: A certain college party is attended by both male and female students. The ratio of male to female students is 3 to 5. If 5 of the male students were to leave the party, the ratio would change to 1 to 2. How many total students are at the party?
(A) 24 (B) 30 (C) 48 (D) 64 (E) 80
Kudos for a correct solution. MANHATTAN GMAT OFFICIAL SOLUTION:Of course, we could set up equations for the unknowns in the problem and solve them algebraically. However, it may be easier just to test the answer choices. Give this approach a try: (A) 24 students implies 9 male and 15 female students. If 5 male students left the party, the remaining ratio would be 4/14 = 2/7. INCORRECT. (B) 30 students implies 11.25 male and 18.75 female students. These numbers must be integers. INCORRECT. (C) 48 students implies 18 male and 30 female students. If 5 male students left the party, the remaining ratio would be 13/30. INCORRECT. (D) 64 students implies 24 male and 40 female students. If 5 male students left the party, the remaining ratio would be 19/40. INCORRECT. (E) 80 students implies 30 male and 50 female students. If 5 male students left the party, the remaining ratio would be 25/50 = 1/2. CORRECT. We proved that the correct answer must be (E) without doing any algebra at all. A nice thing about Testing Answer Choices is that it doesn't require any fundamental knowledge or theory. You don't need to know a special formula. Instead, it forces you to concentrate on the available answer options. It also steadily reduces your uncertainty, since you eliminate wrong answer choices one by one. A question might contain a phrase such as “Which of the following…” This is a great time to test choices Can you please explain how we are choosing values here?
_________________
Thanks & Regards, Anaira Mitch



Manager
Joined: 12 Jun 2016
Posts: 214
Location: India
Concentration: Technology, Leadership
WE: Sales (Telecommunications)

Re: A certain college party is attended by both male and female students.
[#permalink]
Show Tags
07 Aug 2017, 01:54
Hello anairamitch1804, Here are the detailed steps for option A. Rest follow the same approch Given: Male : Female = 3:5. Lets assume actual numbers to be 3x and 5x. Total students = 3x+5x = 8x. Now from the answer choices we get A. 8x = 24 => x = 3 => Male = 3x = 9 and female = 5x = 15. If 5 Male left, the new values of male = 95 = 4. There is no change in females. New Ratio of Male : Female = 4:15 ≠ 1:2. So, A is incorrect. I think the highlighted portion below is a Typo error. Hope this helps and this not too late a response anairamitch1804 wrote: Bunuel wrote: Bunuel wrote: A certain college party is attended by both male and female students. The ratio of male to female students is 3 to 5. If 5 of the male students were to leave the party, the ratio would change to 1 to 2. How many total students are at the party?
(A) 24 (B) 30 (C) 48 (D) 64 (E) 80
Kudos for a correct solution. MANHATTAN GMAT OFFICIAL SOLUTION:Of course, we could set up equations for the unknowns in the problem and solve them algebraically. However, it may be easier just to test the answer choices. Give this approach a try: (A) 24 students implies 9 male and 15 female students. If 5 male students left the party, the remaining ratio would be 4/14 = 2/7. INCORRECT. (B) 30 students implies 11.25 male and 18.75 female students. These numbers must be integers. INCORRECT. (C) 48 students implies 18 male and 30 female students. If 5 male students left the party, the remaining ratio would be 13/30. INCORRECT. (D) 64 students implies 24 male and 40 female students. If 5 male students left the party, the remaining ratio would be 19/40. INCORRECT. (E) 80 students implies 30 male and 50 female students. If 5 male students left the party, the remaining ratio would be 25/50 = 1/2. CORRECT. We proved that the correct answer must be (E) without doing any algebra at all. A nice thing about Testing Answer Choices is that it doesn't require any fundamental knowledge or theory. You don't need to know a special formula. Instead, it forces you to concentrate on the available answer options. It also steadily reduces your uncertainty, since you eliminate wrong answer choices one by one. A question might contain a phrase such as “Which of the following…” This is a great time to test choices Can you please explain how we are choosing values here?
_________________



Target Test Prep Representative
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 6239
Location: United States (CA)

Re: A certain college party is attended by both male and female students.
[#permalink]
Show Tags
10 Aug 2017, 10:42
Bunuel wrote: A certain college party is attended by both male and female students. The ratio of male to female students is 3 to 5. If 5 of the male students were to leave the party, the ratio would change to 1 to 2. How many total students are at the party?
(A) 24 (B) 30 (C) 48 (D) 64 (E) 80 We can let the ratio of male to female = 3x to 5x and create the following equation: (3x  5)/5x = 1/2 2(3x  5) = 5x 6x  10 = 5x 10 = x So, there are 3(10) + 5(10) = 80 total students at the party. Answer: E
_________________
5star rated online GMAT quant self study course See why Target Test Prep is the top rated GMAT quant course on GMAT Club. Read Our Reviews If you find one of my posts helpful, please take a moment to click on the "Kudos" button.




Re: A certain college party is attended by both male and female students.
[#permalink]
10 Aug 2017, 10:42






