GMAT Prep 1_ PS Word Prob #31

This topic has expert replies
Senior | Next Rank: 100 Posts
Posts: 70
Joined: Wed Jan 04, 2012 5:15 pm

GMAT Prep 1_ PS Word Prob #31

by kwah » Wed Mar 07, 2012 8:51 pm
What is the most efficient way to achieve this answer (attachment provided). Please advise, thank you.

I believe I am using a long route...

= x + x + 0.25 + x + 0.50 + x + 0.75 + x + 1 + x + 1.25

Therefore,
6x + 3.75 = 8.25
x = 0.75

Plug into (x + 1.25)

Answer C
Attachments
GMAT Prep 1_ PS Word Prob #31.docx
(56.9 KiB) Downloaded 113 times
Source: — Problem Solving |

User avatar
GMAT Instructor
Posts: 15539
Joined: Tue May 25, 2010 12:04 pm
Location: New York, NY
Thanked: 13060 times
Followed by:1906 members
GMAT Score:790

by GMATGuruNY » Thu Mar 08, 2012 4:10 am
Mark bought a set of 6 flower pots of different sizes at a total cost of $8.25. Each pot cost 0.25 more than the next one below it in size. What was the cost, in dollars, of the largest pot?

A. $1.75
B. $1.85
C. $2.00
D. $2.15
E. $2.30
The prices are evenly spaced integers, with a difference of 25 cents from one price to the next.
With evenly spaced integers, average = median = sum/number.
Thus, the median of the 6 prices = 825/6 ≈ 137.
Since the total is a multiple of 25, and the difference from one price to the next is 25, each price must be a multiple of 25.
Since the median is 137, the 3 most expensive prices are 150, 175, and 200.

The correct answer is C.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.

As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.

For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3

User avatar
Master | Next Rank: 500 Posts
Posts: 425
Joined: Wed Dec 08, 2010 9:00 am
Thanked: 56 times
Followed by:7 members
GMAT Score:690

by LalaB » Thu Mar 08, 2012 8:11 am
it is just a consecutive set

x+ (x+.025)+...+(x+0.25*5) =8.25

Sum=((a1+an)/2)*n
8.25=6*(x+(x+0.25*5))/2

x=0.75

0.75+0.25*5=2

the 2nd approach

since it is a consecutive set, then mean=median
mean=8.25/6
median =(3d +4nd terms)/2 =(x+0.25*2+x+0.25*3)/2=(2x+1.25)/2

(2x+1.25)/2=8.25/6
x=0.75
0.75+0.25*5=2
Happy are those who dream dreams and are ready to pay the price to make them come true.(c)

In order to succeed, your desire for success should be greater than your fear of failure.(c)