BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

averages

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Junior | Next Rank: 30 Posts
Posts: 21
Joined: Tue Feb 26, 2008 1:04 am

averages

by kumard24 » Wed Apr 02, 2008 8:57 am
Month Average Price per Dozen
April $1.26
May $1.20
June $1.08


19. The table above shows the average (arithmetic mean) price per dozen of the large grade A eggs sold in a certain store during three successive months. If as many dozen were sold in April as in May, and twice as many were sold in June as in April, what was the average price per dozen of the eggs sold over the three-month period?
(A) $1.08
(B) $1.10
(C) $1.14
(D) $1.16
(E) $1.18
Top
Source: — Problem Solving |
User avatar
Legendary Member
Posts: 566
Joined: Fri Jan 04, 2008 11:01 am
Location: Philadelphia
Thanked: 31 times
GMAT Score:640

by AleksandrM » Wed Apr 02, 2008 9:32 am
This seems way too easy to me, so I think that I am wrong. However, here is what I did.

A = S/n, therefore, S = 126n; S = 120n; S = 54n Then,

126n + 120n + 2(54n)/n + n + n

354n/3n = 118 -----------> therefore, 1.18 is the average. I'll go w/ E.
Top
User avatar
Master | Next Rank: 500 Posts
Posts: 423
Joined: Thu Dec 27, 2007 1:29 am
Location: Hyderabad, India
Thanked: 36 times
Followed by:2 members
GMAT Score:770

by simplyjat » Wed Apr 02, 2008 9:44 am
For illustration just assume that one dozen were sold in April and May, and two dozen were sold in June(you can also pick n, n and 2n) . These values adhere to constraints given in the question.
now average = (1.26 + 1.20 + 1.08 + 1.08) / 4.
Using this we get an answer 1.155. and that is not given in the answer choices. so there is a .02 missing from the total, check the values again in the question.

AleksandrM, You went wrong at two places. Firstly you can not half the average value in June. The value is average, not total. Secondly, you divided by 3n instead of 4n.
simplyjat
Top
User avatar
Legendary Member
Posts: 566
Joined: Fri Jan 04, 2008 11:01 am
Location: Philadelphia
Thanked: 31 times
GMAT Score:640

by AleksandrM » Wed Apr 02, 2008 9:54 am
You are absolutely right. I should have checked my setup to see whether it made logical sense. June should have been 216 instead a return to 108. The 3n was a stupid mistake because I had THREE months figure stuck in my head.

When you actually double the June figure, you will end up with 462n/4n and this will give you 1.155, which I guess could be rounded off to $1.16, but again, this figure is not in the answer choices.

Good call. Thanks.
Top
Senior | Next Rank: 100 Posts
Posts: 72
Joined: Mon Mar 10, 2008 10:29 am
Thanked: 25 times

by tmmyc » Wed Apr 02, 2008 10:08 am
I also got 1.155, which rounds to 1.16, so the answer should be D.
Top
User avatar
GMAT Instructor
Posts: 3225
Joined: Tue Jan 08, 2008 2:40 pm
Location: Toronto
Thanked: 1710 times
Followed by:614 members
GMAT Score:800

by Stuart@KaplanGMAT » Wed Apr 02, 2008 1:21 pm
Here's a different way to think about it:

Half of the eggs were sold in April/May, half in June (and April=May for numbers).

If we take the average price for April/May, we get $1.23. The average price for June is $1.08.

Each of those accounts for half the eggs sold: therefore, the overall average will simply be the average of those two figures.

($1.23 + $1.08)/2 = $2.31/2 - $1.155: choose (D)
Image

Stuart Kovinsky | Kaplan GMAT Faculty | Toronto

Kaplan Exclusive: The Official Test Day Experience | Ready to Take a Free Practice Test? | Kaplan/Beat the GMAT Member Discount
BTG100 for $100 off a full course
Top
Post new topic Post Reply
• Page 1 of 1