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

It is currently 24 Sep 2016, 23:06
GMAT Club Tests

Close

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
Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

Of the final grades received by the students in a certain

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

1 KUDOS received
Manager
Manager
avatar
Joined: 02 Dec 2012
Posts: 178
Followers: 4

Kudos [?]: 1975 [1] , given: 0

Of the final grades received by the students in a certain [#permalink]

Show Tags

New post 26 Dec 2012, 07:04
1
This post received
KUDOS
2
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  5% (low)

Question Stats:

94% (01:57) correct 6% (01:36) wrong based on 658 sessions

HideShow timer Statistics

Of the final grades received by the students in a certain math course, 1/5 are A's, 1/4 are B's, 1/2 are C's, and the remaining 10 grades are D's. What is the number of students in the course?

(A) 80
(B) 110
(C) 160
(D) 200
(E) 400
[Reveal] Spoiler: OA
Expert Post
3 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 34817
Followers: 6476

Kudos [?]: 82538 [3] , given: 10107

Re: Of the final grades received by the students in a certain [#permalink]

Show Tags

New post 26 Dec 2012, 07:08
3
This post received
KUDOS
Expert's post
Walkabout wrote:
Of the final grades received by the students in a certain math course, 1/5 are A's, 1/4 are B's, 1/2 are C's, and the remaining 10 grades are D's. What is the number of students in the course?

(A) 80
(B) 110
(C) 160
(D) 200
(E) 400


1/5+1/4+1/2=19/20 of the grades are A, B, or C.

Thus the remaining 10 grades represent 1/20 of the grades. Theretofore there are 20*10=200 students.

Answer: D.
_________________

New to the Math Forum?
Please read this: All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

3 KUDOS received
Current Student
avatar
Joined: 21 Oct 2013
Posts: 194
Location: Germany
GMAT 1: 660 Q45 V36
GPA: 3.51
Followers: 1

Kudos [?]: 32 [3] , given: 19

Re: Of the final grades received by the students in a certain [#permalink]

Show Tags

New post 17 Mar 2014, 23:00
3
This post received
KUDOS
Let total number of students be t.

Then
1/5t + 1/4t + 1/2t + 10 = t
solve
10 = t - 1/5t - 1/4t - 1/2t
10 = 1/20t
200 = t

Answer D.
Senior Manager
Senior Manager
User avatar
Status: Math is psycho-logical
Joined: 07 Apr 2014
Posts: 443
Location: Netherlands
GMAT Date: 02-11-2015
WE: Psychology and Counseling (Other)
Followers: 2

Kudos [?]: 94 [0], given: 169

Of the final grades received by the students in a certain [#permalink]

Show Tags

New post 20 Jan 2015, 05:04
I guess the more staightforward way to do this is giving a variable for the total number of students, say T:

Then:
(1/5)T + (1/4)T + (1/2)T + 10 = T
T/5 + T/4 + T/2 + 10 = T
(4T + 5T + 10T) / 20 = T - 10 --> we multiplied with the LCM and moved 10 to the other side.
19T = 20 (T - 10)
19T = 20T - 200
T = 200, ANS D
Expert Post
3 KUDOS received
EMPOWERgmat Instructor
User avatar
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 7460
Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: 340 Q170 V170
Followers: 330

Kudos [?]: 2207 [3] , given: 162

Of the final grades received by the students in a certain [#permalink]

Show Tags

New post 20 Jan 2015, 20:58
3
This post received
KUDOS
Expert's post
HI All,

If you plan to take a "math approach" to this question, you might find that converting the fractions to decimals saves you some work:

1/5 = .2 are As
1/4 = .25 are Bs
1/2 = .5 are Cs
X = Total grades given

Sub-Total = .95(X) of the grades are A/B/C, so the other .05(X) are Ds

.05(X) = 10
5X = 1,000
X = 200

Final Answer:
[Reveal] Spoiler:
D


GMAT assassins aren't born, they're made,
Rich
_________________

Rich Cohen

Co-Founder & GMAT Assassin

Special Offer: Save $75 + GMAT Club Tests

60-point improvement guarantee
www.empowergmat.com/

***********************Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!***********************

1 KUDOS received
Director
Director
User avatar
Joined: 10 Mar 2013
Posts: 608
Location: Germany
Concentration: Finance, Entrepreneurship
GMAT 1: 580 Q46 V24
GPA: 3.88
WE: Information Technology (Consulting)
Followers: 9

Kudos [?]: 198 [1] , given: 200

GMAT ToolKit User
Re: Of the final grades received by the students in a certain [#permalink]

Show Tags

New post 20 May 2015, 12:44
1
This post received
KUDOS
I would rather use decimals for this question.
Grades A:0,2, B:0,25, C:0,5 and the remaining(0,2+0,25+0,5=0,95) 0,05*X=10 --> So, X=200 (D)
_________________

When you’re up, your friends know who you are. When you’re down, you know who your friends are.

Share some Kudos, if my posts help you. Thank you !

800Score ONLY QUANT CAT1 51, CAT2 50, CAT3 50
GMAT PREP 670
MGMAT CAT 630
KAPLAN CAT 660

Expert Post
EMPOWERgmat Instructor
User avatar
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 7460
Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: 340 Q170 V170
Followers: 330

Kudos [?]: 2207 [0], given: 162

Re: Of the final grades received by the students in a certain [#permalink]

Show Tags

New post 22 May 2015, 23:33
Hi All,

This question can also be solved by TESTing THE ANSWERS.

We're given data on the "breakdown" of grades in a course: 1/5 are A's, 1/4 are B's, 1/2 are C's, and the remaining 10 grades are D's. We're asked for the total number of students in the course.

Let's TEST Answer C: 160 students

Total = 160
1/5 are A's = 32
1/4 are B's = 40
1/2 are C's = 80
Sub-total = 152, which leaves 8 students with D's. This is TOO LOW (there are supposed to be 10 students with D's). Thus we need MORE total students.
Eliminate Answers A, B and C.

Since 8 is relatively close to 10, we probably don't need that many more students, so let's TEST D next....

Answer D: 200 students

Total = 200
1/5 are A's = 40
1/4 are B's = 50
1/2 are C's = 100
Sub-total = 190, leaving 10 for D's. This is a MATCH for what we were told, so this MUST be the answer.

Final Answer:
[Reveal] Spoiler:
D


GMAT assassins aren't born, they're made,
Rich
_________________

Rich Cohen

Co-Founder & GMAT Assassin

Special Offer: Save $75 + GMAT Club Tests

60-point improvement guarantee
www.empowergmat.com/

***********************Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!***********************

Manager
Manager
User avatar
Joined: 20 Oct 2015
Posts: 51
Followers: 0

Kudos [?]: 1 [0], given: 8

Re: Of the final grades received by the students in a certain [#permalink]

Show Tags

New post 05 Jul 2016, 06:13
Walkabout wrote:
Of the final grades received by the students in a certain math course, 1/5 are A's, 1/4 are B's, 1/2 are C's, and the remaining 10 grades are D's. What is the number of students in the course?

(A) 80
(B) 110
(C) 160
(D) 200
(E) 400





1/5 + 1/4 + 1/2 + x =1=T somehow

x= 1/20

1/20 T=10

T=200
Manager
Manager
User avatar
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 239
Followers: 11

Kudos [?]: 50 [0], given: 2

Re: Of the final grades received by the students in a certain [#permalink]

Show Tags

New post 07 Jul 2016, 10:17
Walkabout wrote:
Of the final grades received by the students in a certain math course, 1/5 are A's, 1/4 are B's, 1/2 are C's, and the remaining 10 grades are D's. What is the number of students in the course?

(A) 80
(B) 110
(C) 160
(D) 200
(E) 400


We start by creating a variable for the total number of students in the math course. We can say:

T = Total number of students in the math course

Next, we can use variable T in an equation that we translate from the given information. We are given that, of the final grades received by the students in a certain math course, 1/5 are A's, 1/4 are B's, 1/2 are C's, and the remaining 10 grades are D's. Since this represents all the grades in the class, it represents all the students in the class. Thus we know:

#A’s + #B’s + #C’s + #D’s = Total number of students in the class

1/5(T) + ¼(T) + ½(T) + 10 = T

We can multiply the entire equation by 20 to cancel out the denominators of the fractions and we have:

4T + 5T + 10T + 200 = 20T

19T + 200 = 20T

200 = T

There are a total of 200 students in the math class.

Answer is D.
_________________

Image
Jeffrey Miller
Jeffrey Miller
Head of GMAT Instruction

Re: Of the final grades received by the students in a certain   [#permalink] 07 Jul 2016, 10:17
    Similar topics Author Replies Last post
Similar
Topics:
1 There are two groups of students in the sixth grade. Gnpth 2 29 Jun 2014, 22:42
5 Experts publish their posts in the topic In Sam’s chemistry class, his final grade consists of lab wo nidhi12 5 06 Jun 2014, 00:36
4 Experts publish their posts in the topic A student's score on the final test in a certain course was goodyear2013 5 05 Feb 2014, 12:58
10 In a certain class of students, 25% received A’s on the fina pikachu 9 22 May 2013, 13:28
3 Experts publish their posts in the topic In a psychology school the grade of the students is determin AtifS 6 06 Mar 2010, 00:20
Display posts from previous: Sort by

Of the final grades received by the students in a certain

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group and phpBB SEO

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.