Of the final grades received by the students in a certain : GMAT Problem Solving (PS)
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 16 Jan 2017, 22:29

### 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

# Of the final grades received by the students in a certain

Author Message
TAGS:

### Hide Tags

Manager
Joined: 02 Dec 2012
Posts: 178
Followers: 5

Kudos [?]: 2316 [1] , given: 0

### Show Tags

26 Dec 2012, 06:04
1
KUDOS
2
This post was
BOOKMARKED
00:00

Difficulty:

5% (low)

Question Stats:

94% (01:58) correct 6% (01:28) wrong based on 743 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
Math Expert
Joined: 02 Sep 2009
Posts: 36520
Followers: 7067

Kudos [?]: 92939 [3] , given: 10528

### Show Tags

26 Dec 2012, 06:08
3
KUDOS
Expert's post
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.

_________________
Current Student
Joined: 21 Oct 2013
Posts: 194
Location: Germany
GMAT 1: 660 Q45 V36
GPA: 3.51
Followers: 1

Kudos [?]: 37 [3] , given: 19

### Show Tags

17 Mar 2014, 22:00
3
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

Senior Manager
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 [?]: 109 [0], given: 169

### Show Tags

20 Jan 2015, 04:04
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
EMPOWERgmat Instructor
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 8269
Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: 340 Q170 V170
Followers: 379

Kudos [?]: 2454 [3] , given: 163

### Show Tags

20 Jan 2015, 19:58
3
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

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

[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!*********************** Director Joined: 10 Mar 2013 Posts: 608 Location: Germany Concentration: Finance, Entrepreneurship GMAT 1: 580 Q46 V24 GPA: 3.88 WE: Information Technology (Consulting) Followers: 15 Kudos [?]: 266 [1] , given: 200 Re: Of the final grades received by the students in a certain [#permalink] ### Show Tags 20 May 2015, 11:44 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 EMPOWERgmat Instructor Status: GMAT Assassin/Co-Founder Affiliations: EMPOWERgmat Joined: 19 Dec 2014 Posts: 8269 Location: United States (CA) GMAT 1: 800 Q51 V49 GRE 1: 340 Q170 V170 Followers: 379 Kudos [?]: 2454 [0], given: 163 Re: Of the final grades received by the students in a certain [#permalink] ### Show Tags 22 May 2015, 22:33 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
Joined: 20 Oct 2015
Posts: 51
Followers: 0

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

### Show Tags

05 Jul 2016, 05:13
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
Senior Manager
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 458
Followers: 22

Kudos [?]: 181 [0], given: 2

### Show Tags

07 Jul 2016, 09:17
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.

_________________

Jeffrey Miller
Jeffrey Miller

Re: Of the final grades received by the students in a certain   [#permalink] 07 Jul 2016, 09:17
Similar topics Replies Last post
Similar
Topics:
1 There are two groups of students in the sixth grade. 2 29 Jun 2014, 21:42
5 In Sam’s chemistry class, his final grade consists of lab wo 5 05 Jun 2014, 23:36
4 A student's score on the final test in a certain course was 5 05 Feb 2014, 11:58
12 In a certain class of students, 25% received A’s on the fina 9 22 May 2013, 12:28
3 In a psychology school the grade of the students is determin 6 05 Mar 2010, 23:20
Display posts from previous: Sort by

# Of the final grades received by the students in a certain

 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®.