NEW HERE? LEARN MORE
closeclose
Last visit was: 26 Apr 2024, 15:06 It is currently 26 Apr 2024, 15:06
Decision Tracker
My Rewards
New posts
New comers' posts

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

A student has an average (arithmetic mean) score of 72 on his first 3

SORT BY:
Date
Kudos
Tags:
Find Similar Topics 
Show Tags
Hide Tags
User avatar
L
Bunuel
Math Expert
Joined: 02 Sep 2009
Posts: 92948
Own Kudos [?]: 619237 [0]
Given Kudos: 81609
Send PM
CAT Tests Forum Quiz Mode
A student has an average (arithmetic mean) score of 72 on his first 3 [#permalink] New post   20 Dec 2017, 02:54
Expert Reply
00:00
A
B
C
D
E

Difficulty:

5% (low)

Question Stats:

88% (01:08) correct 13% (00:54) wrong based on 79 sessions
Hide Show timer Statistics
A student has an average (arithmetic mean) score of 72 on his first 3 tests. Which of the following is the least average score needed on his next two tests to bring his overall average to at least an 80?

A. 89
B. 90
C. 91
D. 92
E. 104
ShowHide Answer
Official Answer
D
User avatar
B
sumit411
Manager
Manager
Joined: 07 Oct 2017
Posts: 218
Own Kudos [?]: 213 [0]
Given Kudos: 3
Send PM
Re: A student has an average (arithmetic mean) score of 72 on his first 3 [#permalink] New post   20 Dec 2017, 05:32
Imo D

Weighted averages
(72*3 + 2x)/ 7 >=80

X>=92

Sent from my ONEPLUS A3003 using GMAT Club Forum mobile app
User avatar
L
KarishmaB
Tutor
Joined: 16 Oct 2010
Posts: 14831
Own Kudos [?]: 64940 [0]
Given Kudos: 427
Location: Pune, India
Send PM
Re: A student has an average (arithmetic mean) score of 72 on his first 3 [#permalink] New post   20 Dec 2017, 05:43
Expert Reply
Bunuel wrote:
A student has an average (arithmetic mean) score of 72 on his first 3 tests. Which of the following is the least average score needed on his next two tests to bring his overall average to at least an 80?

A. 89
B. 90
C. 91
D. 92
E. 104


Use our standard weighted averages formula:
3/2 = (x - 80)/(80 - 72)
x = 92

Answer (D)
User avatar
L
AkshdeepS
VP
VP
Joined: 13 Apr 2013
Status:It's near - I can see.
Posts: 1479
Own Kudos [?]: 1603 [0]
Given Kudos: 1002
Location: India
Concentration: International Business, Operations
GPA: 3.01
WE:Engineering (Real Estate)
Send PM
Reviews Badge
A student has an average (arithmetic mean) score of 72 on his first 3 [#permalink] New post   20 Dec 2017, 09:38
Bunuel wrote:
A student has an average (arithmetic mean) score of 72 on his first 3 tests. Which of the following is the least average score needed on his next two tests to bring his overall average to at least an 80?

A. 89
B. 90
C. 91
D. 92
E. 104


Try Plug In answer choices

Start with centre (C) = 91

Total score = (72 x 3 + 91 x 2)/5 = 398/5 = 79.6 < 80 Eliminate

Now, we know that we need a slightly greater number than 91

Try (D) = 92

Total score = (72 x 3 + 92 x 2)/5 = 400/5 = 80 = 80

Answer (D) = 92
GMAT Club Bot
gmatclubot
A student has an average (arithmetic mean) score of 72 on his first 3 [#permalink]
20 Dec 2017, 09:38
Moderators:
Bunuel
Math Expert
92948 posts
yashikaaggarwal
Senior Moderator - Masters Forum
3137 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne
Main navigation
GMAT Resources
Partners
MBA Resources
www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions