GMAT Data Sufficiency Discussions

MBA GMAT
775
Gcf * lcm = m*p
60= 3*2*5*2
numbers are 6 and 10

So we can find de rem...

Whtz de Oa?

From stem 1: let nos be m = 4 and p = 6 (as GCF is 2)
p/m = 6/4 = Rem (2). We can chk that rem is always >1 for any values of m and p with given condition. A is suff

From stem 2: nos can be m = 5 and p = 6
Rem(p/m) > 1
for another set, m = 6 and p = 15; again p/m = Rem (>1)
B is suff

Hence D

was the oa?
776
From stem 1: let nos be m = 4 and p = 6 (as GCF is 2)
p/m = 6/4 = Rem (2). We can chk that rem is always >1 for any values of m and p with given condition. A is suff

From stem 2: nos can be m = 5 and p = 6
Rem(p/m) > 1
for another set, m = 6 and p = 15; again p/m = Rem (>1)
B is suff

Hence D

was the oa?


Thanks a lot for ur help.. the OA is A)..because of ur explanation i have understood the logic... for stem 2 :- if u take nos as 5 and 6..then remainder is 1...hence b is insufficient..OA is A)
777
A certain list consists of several different integers. Is the product of the all the integers in the list positive?

1. The product of the greatest and smallest integer in the list is positive.
2. There is an even number of integers in the list.
-------------------------------------------------------------------
Is the three-digit number n less than 550?

1) The product of the digits in n is 30
2) The sum of digits in n is 10
------------------------------------------------------------------
x, 3, 1, 12, 8

If x is an integer, is the median of the 5 numbers greater than the average (arithmetic mean) of the 5 numbers?

(1) x>6
(2) x is greater than the median of the 5 numbers

1. Is the product of the all the integers in the list positive ?

Dont assume at anytime that the numbers are consecutive.

Option 1: The product of the greatest and smallest integer in the list is positive.
Both greatest and smallest integer will be either positive or negative but no info about all other numbers. Not sufficient.
Option 2: There is an even number of integers in the list.
Again no relevant result can be reached at. Not sufficient.
Option 1 and 2: Considering both options we can say that either both the greatest and smallest integer will be positive or both will be negative and as there are even number of integers in the list, the product of all of them will always be positive. Sufficient

hence, C will be the answer.

2. Option 1: The product of the digits in n is 30
The number can be 516 or 615. Not suffficient.
Option 2: The sum of digits in n is 10
The number n can be 307 or 703. Not sufficient.
Option 1 and 2: Number can only be 235, 352 or 532 and their combinations. All of them will be smaller than 550. Sufficient.

Hence, C will be the answer.

3. Is median of 5 numbers greater than average of the same 5 numbers

Option 1: x>6
Average will be greater if x = 200 and median will be greater if x = 7. Not sufficient.
Option2: x is greater than the median of the 5 numbers
Average will be greater if x = 200 and median will be greater if x = 9. Not sufficient.
Option 1 and 2: Average will be greater if x = 200 and median will be greater if x = 9. Not sufficient.

Hence, answer will be E.

Hope it helps!
778

Is n/15 an integer?

1) 3n/15 is an integer
2)8n/15 is an integer

779
Is n/15 an integer?

1) 3n/15 is an integer
2)8n/15 is an integer


Option 1: 3n/15 is an integer
This means n can be 5 or 15 and hence we can't be sure if n/15 is an integer.

Option 2: 8n/15 can be an integer iff n is atleast 15 or a factor of 15, hence n/15 will be an integer.

B should be the answer.

Whats the OA ?
780
Is n/15 an integer?

1) 3n/15 is an integer
2)8n/15 is an integer


stmt 1- 3n/15.. the lease values of n for which this can be an integer are n =5, 15... if n=5, n/15 cant be an integer .. but when n=15.. n/15 is an integer... so not sufficient..

stmt 2 - 8n/15.. the least value for n=15, and multiples of 15.... so n/15 is an integer for sure...

My take...'B'.
781
Option 1: 3n/15 is an integer
This means n can be 5 or 15 and hence we can't be sure if n/15 is an integer.

Option 2: 8n/15 can be an integer iff n is atleast 15 or a factor of 15, hence n/15 will be an integer.

B should be the answer.

Whats the OA ?

B indeed!
Thtz the OA
782

-What is the value of xy?
(1) y = x + 1
(2) y = x^2 + 1

-Is m != n (m not equal to n)?
(1) m + n (2) mn
Can someone provide ans & expln of the above probs?

Thanks,
Ankit

783
-What is the value of xy?
(1) y = x + 1
(2) y = x^2 + 1

-Is m != n (m not equal to n)?
(1) m + n (2) mn
Can someone provide ans & expln of the above probs?

Thanks,
Ankit

My Take:

1. E

stmt 1 -> y = x+1 => xy can be anything..not sufficient
stmt 2 -> y = x^2 + 1 => xy can be anything..not sufficient

Combining... x + 1 = x^2 + 1
=> x - x^2 = 0
=> x (1-x) = 0
=> x = 0 or 1

x = 0, y = 1, xy = 0
x = 1, y = 2, xy = 2

so not sufficient

2. 'B'

stmt 1: m + n
stmt 2: m n m and n should be of differnt signs, => they should be different ===> Sufficient.

Hope it helps
784
-What is the value of xy?
(1) y = x + 1
(2) y = x^2 + 1

-Is m != n (m not equal to n)?
(1) m + n (2) mn
Can someone provide ans & expln of the above probs?

Thanks,
Ankit

1. What is the value of xy?

Option 1: There can be multiple combinations for x and y. Not sufficient.

Option 2: Again, there can be multiple combinations for x and y. Not sufficient.

Option 1 and 2 : x^2 + 1 = x + 1 => X^2 = x => x = 1 or 0. And y can be 1 or 2. So, again different values of xy is possible. Not sufficient.

Answer should be E.
Moral : In DS questions, try to put 0 as one of the value unless and until its specified as non-zero. It helps many times.
2. Is m != n

Option 1: m + n m
Option 2: mn This is only possible when either m or n is less than zero and the other one is greater than zero. So, they are not equal. Sufficient.

Answer should be D.

Whats the OA ?
785
1. What is the value of xy?

Option 1: There can be multiple combinations for x and y. Not sufficient.

Option 2: Again, there can be multiple combinations for x and y. Not sufficient.

Option 1 and 2 : x^2 + 1 = x + 1 => X^2 = x => x = 1 or 0. And y can be 1 or 2. So, again different values of xy is possible. Not sufficient.

Answer should be E.
Moral : In DS questions, try to put 0 as one of the value unless and until its specified as non-zero. It helps many times.
2. Is m != n

Option 1: m + n m
Option 2: mn This is only possible when either m or n is less than zero and the other one is greater than zero. So, they are not equal. Sufficient.

Answer should be D.

Whats the OA ?


@Dopa .....

Quick question.. my guess is the question it self asked m is equal or not to n. so we should consider whether the inequalities provided in the stmt 1 and stmt can exist.. if we take m =n.

stmt 1, 2n
stmt t n^2
please correct me if iam wrong.

Thanks
786
@Dopa .....

Quick question.. my guess is the question it self asked m is equal or not to n. so we should consider whether the inequalities provided in the stmt 1 and stmt can exist.. if we take m =n.

stmt 1, 2n
stmt t n^2
please correct me if iam wrong.

Thanks


You are absolutely correct dude!

I missed that point completely... both m and n can be negative and different/same integers and the inequality will hold true in both case so we can't be sure as whether m and n are same or not

So, B will be the answer.

Thanks dude for whacking me. ;)

Btw when is your GMAT date and hows the preparation ?
787
You are absolutely correct dude!

I missed that point completely... both m and n can be negative and different/same integers and the inequality will hold true in both case so we can't be sure as whether m and n are same or not

So, B will be the answer.

Thanks dude for whacking me. ;)

Btw when is your GMAT date and hows the preparation ?


Well. I see your good answers.. hence, for a sec I thought i was wrong :idea:.
anyways... my G-Day is near by.. prep'ed for close to 3 months... lets see.. wht happens.. hope urs is up too full speed ..
788
My Take:

1. E

stmt 1 -> y = x+1 => xy can be anything..not sufficient
stmt 2 -> y = x^2 + 1 => xy can be anything..not sufficient

Combining... x + 1 = x^2 + 1
=> x - x^2 = 0
=> x (1-x) = 0
=> x = 0 or 1

x = 0, y = 1, xy = 0
x = 1, y = 2, xy = 2

so not sufficient

2. 'B'

stmt 1: m + n
stmt 2: m n m and n should be of differnt signs, => they should be different ===> Sufficient.

Hope it helps


Agree completely with the explanation
789

Committee X and Committee Y , which have no common members, will combine to form Committee Z . Does Committee X have more members than Committee Y ?
(1) The average (arithmetic mean) age of the members of Committee X is 25.7 years and the average age of the members of Committee Y is 29.3 years.
(2) The average (arithmetic mean) age of the members of Committee Z will be 26.6 years.

790

Hi Guys,

Need ur help.......

1. Is the measure of one of the interior angles of quadrilateral ABCD equal to 60 degrees?
(1) Two of the interior angles of ABCD are right angles.
(2) The degree measure of angle ABC is twice the degree measure of angle BCD.

(A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
(B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
(C) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
(D) EACH statement ALONE is sufficient.
(E) Statements (1) and (2) TOGETHER are NOT sufficient.


2. If K is a positive integer, is K the square of an integer?
(1) K is divisible by 4
(2) K is divisible by exactly 4 different prime numbers

(A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
(B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
(C) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
(D) EACH statement ALONE is sufficient.
(E) Statements (1) and (2) TOGETHER are NOT sufficient.


3. Is x
(1) The ratio of x to y is 7/9
(2) xy>0

(A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
(B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
(C) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
(D) EACH statement ALONE is sufficient.
(E) Statements (1) and (2) TOGETHER are NOT sufficient.

4. What is the median number of employees assigned per project for the projects at Company Z?

(1) 25 percent of the projects at Company Z have 4 or more employees assigned to each project.
(2) 35 percent of the projects at Company Z have 2 or fewer employees assigned to each project.

(A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
(B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
(C) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
(D) EACH statement ALONE is sufficient.
(E) Statements (1) and (2) TOGETHER are NOT sufficient.

791
Hi Guys,

Need ur help.......

1. Is the measure of one of the interior angles of quadrilateral ABCD equal to 60 degrees?
(1) Two of the interior angles of ABCD are right angles.
(2) The degree measure of angle ABC is twice the degree measure of angle BCD.
(A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
(B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
(C) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
(D) EACH statement ALONE is sufficient.
(E) Statements (1) and (2) TOGETHER are NOT sufficient.
2. If K is a positive integer, is K the square of an integer?
(1) K is divisible by 4
(2) K is divisible by exactly 4 different prime numbers
(A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
(B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
(C) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
(D) EACH statement ALONE is sufficient.
(E) Statements (1) and (2) TOGETHER are NOT sufficient.
3. Is x
(1) The ratio of x to y is 7/9
(2) xy>0
(A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
(B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
(C) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
(D) EACH statement ALONE is sufficient.
(E) Statements (1) and (2) TOGETHER are NOT sufficient.
4. What is the median number of employees assigned per project for the projects at Company Z?
(1) 25 percent of the projects at Company Z have 4 or more employees assigned to each project.
(2) 35 percent of the projects at Company Z have 2 or fewer employees assigned to each project.
(A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
(B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
(C) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
(D) EACH statement ALONE is sufficient.
(E) Statements (1) and (2) TOGETHER are NOT sufficient.


My picks are E,B,E,C

What are the OA's???
792
My picks are E,B,E,C

What are the OA's???


OA's are E, E, E, C

Would u plz xplain ?
793
Committee X and Committee Y , which have no common members, will combine to form Committee Z . Does Committee X have more members than Committee Y ?
(1) The average (arithmetic mean) age of the members of Committee X is 25.7 years and the average age of the members of Committee Y is 29.3 years.
(2) The average (arithmetic mean) age of the members of Committee Z will be 26.6 years.


My Take 'C'.

1. age is not a factor of how many members must be there.. not sufficient
2. same hold here... not sufficient.

combining.... we can solve....

average age of Z = 26.6 = (total age of X + total age of Y) / (members of X + Y)

Total age of X = 25.7 * a (say 'a' total mems of X)
Total age of Y = 29.3 * b (say 'b' total mems of Y)

26.6 = ( 25.7 a + 29.3 b) / (a+b)
=> 2.7 b = .9 a or a = 3b ......sufficient...
794

Does line S intersect line segment QR?

(1) The equation of line S is y = -x + 4.

(2) The slope of line S is -1.

the figure is attached for reference

my only concern here is can two parallel lines overlap each other

like if i say there is a line segment PQ can we draw a line AB parallel to PQ and passing through points P and Q