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

 It is currently 02 Jul 2015, 13:33

### 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

# A school has only two classes - class X and class Y.

Author Message
TAGS:
Director
Joined: 14 Sep 2005
Posts: 993
Location: South Korea
Followers: 2

Kudos [?]: 49 [0], given: 0

A school has only two classes - class X and class Y.  [#permalink]  20 Dec 2005, 19:52
1
This post was
BOOKMARKED
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
A school has only two classes - class X and class Y.

Students in class X each have two pencils and one pen, and students in class Y each have one pencil and three pens. The average number of peicils each student has is 1.6.

What is the average number of pens each student has?
_________________

Auge um Auge, Zahn um Zahn !

Senior Manager
Joined: 05 Oct 2005
Posts: 485
Followers: 1

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

Re: PS - Average pens [#permalink]  20 Dec 2005, 20:22
gamjatang wrote:
A school has only two classes - class X and class Y.

Students in class X each have two pencils and one pen, and students in class Y each have one pencil and three pens. The average number of peicils each student has is 1.6.

What is the average number of pens each student has?

Student in class X - 2 pencils, 1 pen
Student in class Y - 1 pencil , 3 pens

No. of students in class X = x
No. of students in class Y = y

(2x+y)/(x+y) = 1.6
2x+y = 1.6x + 1.6y
.4x = .6y
x/y = 3/2

Since we know the ratio, we know the proportion.

(1(3) + 3 (2))/(3+2) = 9/5 = 1.8

Avg. no. of pens = 1.8

By the way, gamgatang, thanks for posting these questions, they are very helpful in my prep.
GMAT Club Legend
Joined: 07 Jul 2004
Posts: 5068
Location: Singapore
Followers: 23

Kudos [?]: 193 [0], given: 0

X = 2 pencils, 1 pen
Y = 1 pencil, 3 pens

let number of students in class X be x, and number of students in class Y be y

(2x + y)/x+y = 1.6
2x+y = 1.6x + 1.6y
0.4x - 0.6y = 0
0.4x = 0.6y
x = 1.5y

ave number of pens = x + 3y/(x+y). Since x = 1.5y, so x + 3y/(x+y) = 4.5y/2.5y = 1.8 average number of pens
Similar topics Replies Last post
Similar
Topics:
4 At Didymus Corporation, there are just two classes of employees: silve 5 17 Mar 2015, 04:53
16 A school has 3 classes, math class has 14 students 14 01 Apr 2013, 10:43
8 A class has 12 boys and x girls. Average score of boys and 8 16 Nov 2011, 05:07
A professor gave the same exam to two classes. The 200 4 19 Jun 2008, 04:03
A certain junior class has 1000 students and a certain 3 19 Feb 2006, 12:58
Display posts from previous: Sort by