Last visit was: 24 Apr 2026, 08:28 It is currently 24 Apr 2026, 08:28
Home
Messages
Tests
Schools
Events
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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel
Back to Forum
Create Topic
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 24 Apr 2026
Posts: 109,814
Own Kudos:
811,020
 [1]
Given Kudos: 105,871
Products:
GMAT Club Tests Forum Quiz
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 109,814
Kudos: 811,020
 [1]
An oculist charges $30.00 for an eye examination, frames, and glass 13 Oct 2017, 00:31
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
B
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

5% (low)

Question Stats:

94% (01:19) correct 6% (02:12) wrong based on 105 sessions

History

Date
Time
Result
Not Attempted Yet
An oculist charges $30.00 for an eye examination, frames, and glass lenses, but $42.00 for an eye examination, frames, and plastic lenses. If the plastic lenses cost four times as much as the glass lenses, how much do the glass lenses cost?

A. $2
B. $4
C. $5
D. $6
E. $8
ShowHide Answer
Official Answer
B
Most Helpful Reply
User avatar
raki99
User avatar
Joined: 11 Apr 2017
Last visit: 07 Apr 2021
Posts: 35
Own Kudos:
16
 [6]
Given Kudos: 201
Schools: Kelley '20
Schools: Kelley '20
Posts: 35
Kudos: 16
 [6]
An oculist charges $30.00 for an eye examination, frames, and glass 13 Oct 2017, 01:13
6
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Here,
Glass lense cost= x
plastic lense cost= 4x
So,
4x-x= 12
3x= 12
x= 4

glass lenses cost= 4
General Discussion
User avatar
varun4s
User avatar
Joined: 07 Jul 2012
Last visit: 20 Apr 2026
Posts: 272
Own Kudos:
340
 [3]
Given Kudos: 71
Location: India
Concentration: Finance, Accounting
GPA: 3.5
Posts: 272
Kudos: 340
 [3]
An oculist charges $30.00 for an eye examination, frames, and glass 13 Oct 2017, 02:12
3
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Let Glass lenses cost be x
Plastic lenses cost= 4x
Now, 4x-x= 42-30= 12
3x= 12
x=4
So Glass lenses cost= $4

Answer: B.

Kudos please if you like my explanation!
User avatar
Skywalker18
User avatar
Retired Moderator
Joined: 08 Dec 2013
Last visit: 15 Nov 2023
Posts: 1,973
Own Kudos:
10,169
Given Kudos: 171
Status:Greatness begins beyond your comfort zone
Location: India
Concentration: General Management, Strategy
GPA: 3.2
WE:Information Technology (Consulting)
Products:
My Reviews
Posts: 1,973
Kudos: 10,169
An oculist charges $30.00 for an eye examination, frames, and glass 13 Oct 2017, 21:19
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
An oculist charges $30.00 for an eye examination, frames, and glass lenses, but $42.00 for an eye examination, frames, and plastic lenses. If the plastic lenses cost four times as much as the glass lenses, how much do the glass lenses cost?

A. $2
B. $4
C. $5
D. $6
E. $8
Show more

Let cost of eye examination = E
Frames = F
glass lenses = G
plastic lenses = P

E+F+G = 30
E+F+P = 42
P = 4G
P-G = 12
G = 4

Answer B
User avatar
JeffTargetTestPrep
User avatar
Target Test Prep Representative
Joined: 04 Mar 2011
Last visit: 05 Jan 2024
Posts: 2,974
Own Kudos:
8,711
 [1]
Given Kudos: 1,646
Status:Head GMAT Instructor
Affiliations: Target Test Prep
Expert
Expert reply
Posts: 2,974
Kudos: 8,711
 [1]
An oculist charges $30.00 for an eye examination, frames, and glass 16 Oct 2017, 17:19
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
An oculist charges $30.00 for an eye examination, frames, and glass lenses, but $42.00 for an eye examination, frames, and plastic lenses. If the plastic lenses cost four times as much as the glass lenses, how much do the glass lenses cost?

A. $2
B. $4
C. $5
D. $6
E. $8
Show more

We can let e = the cost for the exam, f = the cost for the frames, g = the cost for the glass lenses, and p = the cost for the plastic lenses. We can create two equations:

30 = e + f + g

and

42 = e + f + p

Subtracting the first equation from the second, we have:

12 = p - g

We also know that p = 4g; thus:

12 = 4g - g

12 = 3g

4 = g

Answer: B
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 38,973
Own Kudos:
1,117
Posts: 38,973
Kudos: 1,117
An oculist charges $30.00 for an eye examination, frames, and glass 13 Jun 2022, 02:01
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Automated notice from GMAT Club BumpBot:

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

This post was generated automatically.
Moderators:
Bunuel
Math Expert
109814 posts
Krunaal
Tuck School Moderator
853 posts