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

Redeem

Data Sufficiency

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Junior | Next Rank: 30 Posts
Posts: 29
Joined: Sun Mar 13, 2011 7:50 pm
Thanked: 1 times

Data Sufficiency

by Tagne » Fri Mar 18, 2011 11:47 pm
1. Is the average (arithmetic mean) of 5 different positive integers atleast 30?
a. Each of the integer is a multiple of 10
b. The sum of the integer is 160

2. IxI = Y - Z ?
a. X + Y = Z
b. X < 0

3. Warehouse Q's revenue from the sale of sofas was what percent greater this year than it was last year?
a. Warehouse W sold 10 percent more sofas this year than it did last year
b. Warehouse W's selling price per sofa was $30 greater this year than it was last year

4. Circle C and line k lie in the xy-plane. If circle C is centered at the origin and has radius 1, does line k intersect c?
a. The x intercept of line k is greater than 1
b. The slope of line k is -1/10
Top
Source: — Problem Solving |
User avatar
Legendary Member
Posts: 582
Joined: Tue Mar 08, 2011 12:48 am
Thanked: 61 times
Followed by:6 members
GMAT Score:740

by force5 » Sat Mar 19, 2011 1:15 am
1. Is the average (arithmetic mean) of 5 different positive integers atleast 30?
a. Each of the integer is a multiple of 10
b. The sum of the integer is 160
IMO D

stmnt A- (sufficient)5 positive integers multiple of 10 will always have average more than 30 ( remember 1st positive integer will be 10)
stment2- (sufficient) if sum is 160 then average 160/5 will always be greater than 30



hope it helps
Top
User avatar
Legendary Member
Posts: 582
Joined: Tue Mar 08, 2011 12:48 am
Thanked: 61 times
Followed by:6 members
GMAT Score:740

by force5 » Sat Mar 19, 2011 1:23 am
2. IxI = Y - Z ?
a. X + Y = Z
b. X < 0
IMO- A

stmnt 1 - ( sufficient) x+y=z
then x = z-y ( when x positive)
x= y-z ( when x negative)
stmnt2- ( insufficient)
Top
User avatar
Legendary Member
Posts: 582
Joined: Tue Mar 08, 2011 12:48 am
Thanked: 61 times
Followed by:6 members
GMAT Score:740

by force5 » Sat Mar 19, 2011 1:28 am
3. Warehouse Q's revenue from the sale of sofas was what percent greater this year than it was last year?
a. Warehouse W sold 10 percent more sofas this year than it did last year
b. Warehouse W's selling price per sofa was $30 greater this year than it was last year

IMO E
we need to find increase/last year's profit

(1) (insuff) if last year is x then this year is 1.1x
required percent is 0.1/x
(2) (insuff) selling price last year y, this year y+30
reqd percent 30/y moreover no info about how many sofa's
combining (insuff)
still 2 variables.

hope it helps
Top

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 3835
Joined: Fri Apr 02, 2010 10:00 pm
Location: Milpitas, CA
Thanked: 1854 times
Followed by:523 members
GMAT Score:770

by Anurag@Gurome » Sat Mar 19, 2011 1:39 am
Tagne wrote:1. Is the average (arithmetic mean) of 5 different positive integers atleast 30?
a. Each of the integer is a multiple of 10
b. The sum of the integer is 160
Statement 1: Minimum possible values of the integers are 10, 20, 30, 40, and 50. Hence minimum possible average is 30.

Sufficient

Statement 2: Sum of the integers = 160 and number of integers = 5
Hence, average = 160/5 = 32

Sufficient

The correct answer is D.
Last edited by Anurag@Gurome on Sat Mar 19, 2011 2:32 am, edited 1 time in total.
Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)

Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/
Top
User avatar
Legendary Member
Posts: 582
Joined: Tue Mar 08, 2011 12:48 am
Thanked: 61 times
Followed by:6 members
GMAT Score:740

by force5 » Sat Mar 19, 2011 1:42 am
4. Circle C and line k lie in the xy-plane. If circle C is centered at the origin and has radius 1, does line k intersect c?
a. The x intercept of line k is greater than 1
b. The slope of line k is -1/10
Good question
IMO- E

lets start with stmnt 2
insuff- info means slope is -ve but no other info about the line. line can be anywhere.
stmnt1- insuff
we dont know what is the slope of the line

combining ( still insuff)
although it seems that C will give the answer. however there can be two scenarios. (1) the point according to stmnt1 lies close to x=1 ( though will still be greater than 1) ... in this case the line will intersect the circle. (2) consider that the point lies too far away on x axis... say x= 100000000000000 then this line will not intersect the circle.

Hope it helps..
Top
User avatar
Legendary Member
Posts: 582
Joined: Tue Mar 08, 2011 12:48 am
Thanked: 61 times
Followed by:6 members
GMAT Score:740

by force5 » Sat Mar 19, 2011 1:44 am
Statement 1: Let's assume following set of integers
1. {0, 10, 20, 30, 40} --> Average = 20
2. {10, 20, 30, 40, 50} --> Average = 30

Not sufficient

Statement 2: Sum of the integers = 160 and number of integers = 5
Hence, average = 160/5 = 32

Sufficient

The correct answer is B.
hi Anurag i think the answer to this question should be D. the integers have to be +ve. Zero is not a positive integer. hence the first integer here will have to be 10...
Top

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 3835
Joined: Fri Apr 02, 2010 10:00 pm
Location: Milpitas, CA
Thanked: 1854 times
Followed by:523 members
GMAT Score:770

by Anurag@Gurome » Sat Mar 19, 2011 1:47 am
Tagne wrote:2. IxI = Y - Z ?
a. X + Y = Z
b. X < 0
Statement 1: x + y = z => x = (z - y)
Now, we have two possible scenarios
  • 1. x ≥ 0 => |x| = x = (z - y) --> Answers the question in NO
    2. x < 0 => |x| = -x = (y - z) --> Answers the question in YES
Not sufficient

Statement 2: No information about y and z --> Not sufficient

1 & 2 Together: Now we know x is negative.
Hence, |x| = -x = (y - z)

Sufficient

The correct answer is C.
Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)

Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/
Top
User avatar
Legendary Member
Posts: 582
Joined: Tue Mar 08, 2011 12:48 am
Thanked: 61 times
Followed by:6 members
GMAT Score:740

by force5 » Sat Mar 19, 2011 2:26 am
MO- A

stmnt 1 - ( sufficient) x+y=z
then x = z-y ( when x positive)
x= y-z ( when x negative)
stmnt2- ( insufficient)
Guys please correct.. the answer should be C. i did make a mistake.


thanks
Top

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 3835
Joined: Fri Apr 02, 2010 10:00 pm
Location: Milpitas, CA
Thanked: 1854 times
Followed by:523 members
GMAT Score:770

by Anurag@Gurome » Sat Mar 19, 2011 2:33 am
force5 wrote:hi Anurag i think the answer to this question should be D. the integers have to be +ve. Zero is not a positive integer. hence the first integer here will have to be 10...
Thanks for the correction.
Edited the reply.
Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)

Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/
Top
User avatar
Newbie | Next Rank: 10 Posts
Posts: 5
Joined: Wed Jun 08, 2011 7:51 am

by KRISH1985 » Fri Jul 22, 2011 12:42 am
Hi Anurag!

One question here, is Zero not a multiple of 10?

If I consider 0,10,20,30,40, then the average is less than 30..

Should we not consider 0 as multiple of number in such questions?
Top
User avatar
Newbie | Next Rank: 10 Posts
Posts: 5
Joined: Wed Jun 08, 2011 7:51 am

by KRISH1985 » Fri Jul 22, 2011 12:55 am
got, positive integers are numbers greater than 0.
Top
User avatar
Master | Next Rank: 500 Posts
Posts: 407
Joined: Tue Jan 25, 2011 9:19 am
Thanked: 25 times
Followed by:7 members

by Ozlemg » Fri Jul 22, 2011 3:28 am
What are the OA of other questions?
The more you suffer before the test, the less you will do so in the test! :)
Top
Legendary Member
Posts: 2789
Joined: Tue Jul 26, 2011 12:19 am
Location: Chennai, India
Thanked: 206 times
Followed by:43 members
GMAT Score:640

by GmatKiss » Sat Aug 06, 2011 5:09 am
IMO:C for Q3,

what is OA?
Top
Post new topic Post Reply
• Page 1 of 1