It is currently 26 Jun 2017, 12:47

### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# New Set: Number Properties!!!

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 39702

### Show Tags

25 Mar 2013, 04:50
22
KUDOS
Expert's post
136
This post was
BOOKMARKED
The next set of medium/hard DS number properties questions. I'll post OA's with detailed explanations on Friday. Please, post your solutions along with the answers.

1. If x is an integer, what is the value of x?

(1) |23x| is a prime number
(2) $$2\sqrt{x^2}$$ is a prime number.

Solution: new-set-number-properties-149775-40.html#p1205341

2. If a positive integer n has exactly two positive factors what is the value of n?

(1) n/2 is one of the factors of n
(2) The lowest common multiple of n and n + 10 is an even number.

Solution: new-set-number-properties-149775-40.html#p1205355

3. If 0 < x < y and x and y are consecutive perfect squares, what is the remainder when y is divided by x?

(1) Both x and y is have 3 positive factors.
(2) Both $$\sqrt{x}$$ and $$\sqrt{y}$$ are prime numbers

Solution: new-set-number-properties-149775-60.html#p1205358

4. Each digit of the three-digit integer K is a positive multiple of 4, what is the value of K?

(1) The units digit of K is the least common multiple of the tens and hundreds digit of K
(2) K is NOT a multiple of 3.

Solution: new-set-number-properties-149775-60.html#p1205361

5. If a, b, and c are integers and a < b < c, are a, b, and c consecutive integers?

(1) The median of {a!, b!, c!} is an odd number.
(2) c! is a prime number

Solution: new-set-number-properties-149775-60.html#p1205364

6. Set S consists of more than two integers. Are all the numbers in set S negative?

(1) The product of any three integers in the list is negative
(2) The product of the smallest and largest integers in the list is a prime number.

Solution: new-set-number-properties-149775-60.html#p1205373

7. Is x the square of an integer?

(1) When x is divided by 12 the remainder is 6
(2) When x is divided by 14 the remainder is 2

Solution: new-set-number-properties-149775-60.html#p1205378

8. Set A consist of 10 terms, each of which is a reciprocal of a prime number, is the median of the set less than 1/5?

(1) Reciprocal of the median is a prime number
(2) The product of any two terms of the set is a terminating decimal

Solution: new-set-number-properties-149775-60.html#p1205382

9. If [x] denotes the greatest integer less than or equal to x for any number x, is [a] + [b] = 1 ?

(1) ab = 2
(2) 0 < a < b < 2

Solution: new-set-number-properties-149775-60.html#p1205389

10. If N = 3^x*5^y, where x and y are positive integers, and N has 12 positive factors, what is the value of N?

(1) 9 is NOT a factor of N
(2) 125 is a factor of N

Solution: new-set-number-properties-149775-60.html#p1205392

BONUS QUESTION:
11. If x and y are positive integers, is x a prime number?

(1) |x - 2| < 2 - y
(2) x + y - 3 = |1-y|

Solution: new-set-number-properties-149775-60.html#p1205398

Kudos points for each correct solution!!!
_________________
Math Expert
Joined: 02 Sep 2009
Posts: 39702
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 04:50
1
KUDOS
Expert's post
1
This post was
BOOKMARKED
Please suggest on what category would you like the next set to be. Thank you!
_________________
Moderator
Joined: 01 Sep 2010
Posts: 3213
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 07:01
1
KUDOS
word problems

Thanks for the set
_________________
VP
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1122
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 07:03
1
KUDOS
If x is an integer, what is the value of x?

(1) |23x| is a prime number
Since 23 si prime,$$x$$can be $$+1$$ or $$-1$$
not sufficient

(2) 2\sqrt{x^2} is a prime number.
once again $$x$$ can be $$+1$$ or $$-1$$
not sufficient

And since 1)+2) provides no new info IMO E
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

VP
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1122
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 07:10
1
KUDOS
2. If a positive integer n has exactly two positive factors what is the value of n?

Number of factors of a number is $$a+1$$ where the number is $$n^a$$
And since n has 2 factors$$n$$ must be prime and$$>1$$

(1) n/2 is one of the factors of n
Only $$2$$ fits these conditions, so $$n=2$$
Sufficient

(2) The lowest common multiple of n and n + 10 is an even number.
Only $$2$$ fits these conditions, so $$n=2$$ once again. $$n$$ IMO is prime so the only prime that respect statement (2) is 2 because all other prime are odd, and odd+even = odd, so the LCM of an odd and an odd is odd in all cases except n=2

IMO D
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

VP
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1122
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 07:24
1
KUDOS
6. Set S consists of more than two integers. Are all the numbers in set S negative?

(1) The product of any three integers in the list is negative
Not sufficient
Example: $$S = {-1,3,5}$$
the product is always <0 but 2 numbers are positive
Example: $$S = {-1,-3,-5}$$
the product is always <0 and all numbers are negative

(2) The product of the smallest and largest integers in the list is a prime number.
Not sufficient
Example: $$S = {1,3,5}$$
$$1*5=5$$ prime but all positive
Example: S = $${-1,-3,-5}$$
$$-1*-5=5$$ prime but all negative

(1)+(2) Sufficient IMO C
Using statement 2 we know that all are positive or all are negative, using statement 1 we know that "at least" 1 is negative=> so all are negative
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

VP
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1122
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 07:30
7. Is x the square of an integer?

(1) When x is divided by 12 the remainder is 6
(2) When x is divided by 14 the remainder is 2

$$x=12q+6$$
$$x=14z+2$$

$$12q+6=14z+2$$
$$6-2=14z-12q$$
$$4=2(7z-6q)$$
$$2=7z-6q$$

$$z=2,q=2$$

$$x=12*2+6=30$$
$$x=14*2+2=30$$

so x is not the square of an integer.IMO C
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

VP
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1122
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 07:40
9. If [x] denotes the greatest integer less than or equal to x for any number x, is [a] + [b] = 1 ?

(1) ab = 2
(2) 0 < a < b < 2

The question can be seen as (given statement 2):
$$[a] + [b] = 1$$
case 1:$$0<(=)a<1$$ => $$[a]=0$$ and $$1(=)<b<2$$ => $$[b]=1$$ so $$[a] + [b] = 1$$
or the opposite
case 2: $$0<(=)b<1$$ => $$[b]=0$$ and $$1(=)<a<2$$ => $$[a]=1$$ so $$[a] + [b] = 1$$

But as ab=2 we know that one term is $$\frac{1}{2}$$ and the other is $$2$$
So we are in one of the two senarios above, IMO C
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

VP
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1122
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 07:49
1
KUDOS
10. If N = 3^x*5^y, where x and y are positive integers, and N has 12 positive factors, what is the value of N?

Number of factors of $$N = (x+1)(y+1) = 12$$
the combinations are
$$3*4$$ with $$x= 2$$ and $$y=3$$
$$6*2$$ with $$x=5$$ and$$y = 1$$
and the "other way round" of each one

(1) 9 is NOT a factor of N
So x must be 1, $$x=1$$
because $$(1+1)(y+1)=12$$
$$y=5$$
Sufficient

(2) 125 is a factor of N
So $$y>=3$$, y can be 3 or 5, NOT sufficient
$$y=3, (3+1)(x+1)=12, x=2$$
$$y=5, (5+1)(x+1)=12, x=1$$

IMO A
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

Last edited by Zarrolou on 25 Mar 2013, 08:57, edited 1 time in total.
VP
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1122
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 08:10
11. If x and y are positive integers, is x a prime number?

(1) |x - 2| < 2 - y
(2) x + y - 3 = |1-y|

This is a GOOD one. IMO C

(1) |x - 2| < 2 - y

$$x-2>0, x>2$$
case 1)$$x>2$$
$$x-2<2-y$$
$$x+y<4$$

case 2)$$0<x<=2$$ ( x is positive )
$$-x+2<2-y$$
$$x>y$$

NOT SUFFICIENT

(2) x + y - 3 = |1-y|

case 1)$$y>1$$
$$x+y-3=1-y$$
$$x+2y=4$$

case 2)$$0<y<=1$$ ( y is positive)
$$x+y-3=-1+y$$
$$x=2$$

NOT SUFFICIENT

Combining 1 and 2 we obtain that

------0------------1----------2----------------
------|~~~~~~x>y~~~~~~~|~~~x+y<4 for the first one
------|~~x=2~~~|~~~~~~x+2y=4~~~~for the second one

And combining all the cases together we obtain
1)$$0<x<=2$$ with $$0<y<=1$$
$$x=2$$ and $$x>y$$ so $$x=2$$ and $$y=1$$
2)$$0<x<=2$$ with $$y>1$$
$$x>y$$ and $$x+2y=4$$, given that x and y are positive $$x=2, y=1$$
3)$$x>2$$ with $$0<y<=1$$
$$x+y<4$$ and $$x=2$$ so $$x=2,y=1$$
4)x>2 with y>1
$$x+y<4$$ and $$x+2y=4$$, $$x=2,y=1$$
In each case $$x=2$$ so x is prime
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

VP
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1122
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 08:23
1
KUDOS
5. If a, b, and c are integers and a < b < c, are a, b, and c consecutive integers?

(1) The median of {a!, b!, c!} is an odd number.
the median of three elements is the one in the middle, so b! is odd
there are only 2 cases in which n! is odd and are if n=1 or if n=0
so b is 0 , 1
Not Sufficient

(2) c! is a prime number
c can once again be 0,1 or in this case 2.
Not sufficient

-This is a weak passage, I don't know if I'm right-

n! is possible only for positive number so given that
a < b < c
c must be 2, b must be 1, and (because of my weak hypothesis a>=0) a must be 0

IMO C
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

VP
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1122
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 08:34
1
KUDOS
8. Set A consist of 10 terms, each of which is a reciprocal of a prime number, is the median of the set less than 1/5?

(1) Reciprocal of the median is a prime number
Not sufficient

(2) The product of any two terms of the set is a terminating decimal
Because $$\frac{1}{prime}$$ is not a terminating decimal, with the only exception of 1/4, 1/1, 1/5 and 1/2
any set made by these three CANNOT have a median < 1/5, it can be = 1/5 but NEVER <
Some examples:
A={1,1,1,1,1/5,1/5,1/5,1/5,1/5,1/5} the median is 1/5 = 1/5
A={1,1,1,1,1/2,1/2,1/2,1/2,1/2,1/2} the median is 1/2 > 1/5
SUFFICIENT

IMO B
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

Verbal Forum Moderator
Joined: 10 Oct 2012
Posts: 629
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 09:35
2
KUDOS
11. If x and y are positive integers, is x a prime number?

(1) |x - 2| < 2 - y
(2) x + y - 3 = |1-y|

We know that x >0 and y>0 and they are integers.

From F.S 1, we have 2-y>=0 or y<=2. Thus y can only be 2 or 1. Now if y=2, we would have 0>some thing positive or 0>0(when x also equal to 2). Either case is not possible. Thus, y can only be 1. For y=1, we can only have x = 2. Which is prime. Sufficient.

From F.S 2, we have either y>1 or y<1. Now as y is a positive integer, y can't be less than 1.For y=1, we anyways have x=2(prime).In the first case, we have y>1--> x+y-3 = y-1 or x=2(prime). Thus, Sufficient.

D.
_________________
Manager
Joined: 26 Feb 2013
Posts: 53
Concentration: Strategy, General Management
GMAT 1: 660 Q50 V30
WE: Consulting (Telecommunications)
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 09:49
1-B
2-A
3-E
4-E
5-B
6-C
7-A
8-D
9-B
10-A
11-D
Verbal Forum Moderator
Joined: 10 Oct 2012
Posts: 629
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 10:06
2
KUDOS
7.Is x the square of an integer?

(1) When x is divided by 12 the remainder is 6
(2) When x is divided by 14 the remainder is 2

From F.S 1, we have x = 12q+6 --> 6(2q+1). For x to be a square of an integer, we should have 2q+1 of the form 6^pk^2, where both q,p and k are integers and p is odd. Now we know that 2q+1 is an odd number and 6^pk^2 is even. Thus they can never be equal and hence x can never be the square of an integer. Sufficient.

From F.S 2, we have x = 14q+2 --> 2(7q+1).Just as above, we should have 7q+1 = 2^pk^2. Now for q=1, k=2 and p=1, we have 8=8, thus x is the square of an integer. But for q=0, x is not. Insufficient.

Basically for the second fact statement, we can plug in easily. No need for the elaborate theory.

A.
_________________
Verbal Forum Moderator
Joined: 10 Oct 2012
Posts: 629
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 11:02
2
KUDOS
5. If a, b, and c are integers and a < b < c, are a, b, and c consecutive integers?

(1) The median of {a!, b!, c!} is an odd number
(2) c! is a prime number

From F.S 1, we have b! = odd, thus b can be 0 or 1.But, as factorial notation is only for positive integers, thus, if b=0, then a would become negative and thus b is only equal to 1.Now, a can only be 0 as we are given that a! exists. But nothing has been mentioned about c. All we know is that c>1 and an integer. Insufficient.

From F.S 2, we have c! is a prime number. Again, c has to be positive and c can only be 2.However, a and b can take any values, even negative. Insufficient.

Taking both together, we have a=0, b=1 and c=2. Sufficient.

C.
_________________
Senior Manager
Status: Final Lap
Joined: 25 Oct 2012
Posts: 286
Concentration: General Management, Entrepreneurship
GPA: 3.54
WE: Project Management (Retail Banking)
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 17:58
1
KUDOS
1. If x is an integer, what is the value of x?

(1) |23x| is a prime number
(2)$$2 \sqrt{x^2}$$ is a prime number.

(1) |23x| is a prime number

For $$x=1$$ $$|23x| = |23*1|$$ --> 23 is prime

For $$x=-1$$ $$|23x| = |23*(-1)|]$$ --> $$|-23| = 23$$ 23 is prime also

Thus, this holds true for two values of x and because of that, the value of x cannot be determined.

(1) INSUFFICIENT

(2)$$2 \sqrt{x^2}$$ is a prime number.
x=-1 --> $$2 \sqrt{x^2}$$ =2 prime
x=1 --> $$2 \sqrt{x^2}$$ =2 prime

Thus, x can take the value of either 1 or -1
(2) INSUFFICIENT

|23x| is a prime number AND $$2 \sqrt{x^2}$$ is a prime number.
For $$x=1$$ 23 is prime and 2 is prime
For $$x=-1$$ 23 is prime and 2 is prime
(1) +(2) INSUFFICIENT

_________________

KUDOS is the good manner to help the entire community.

Senior Manager
Status: Final Lap
Joined: 25 Oct 2012
Posts: 286
Concentration: General Management, Entrepreneurship
GPA: 3.54
WE: Project Management (Retail Banking)
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

25 Mar 2013, 18:13
1
KUDOS
2. If a positive integer n has exactly two positive factors what is the value of n?

(1) n/2 is one of the factors of n
(2) The lowest common multiple of n and n + 10 is an even number.

n is a positive integer that has exactly two positive factors --> 1 must be one of its factor --> n is a prime number and not equal to 1 (because 1 has only one positive factors, itself)

So these two factors could be (1,2) or (1,3) or (1,5) ... and n could be 2,3,5 .......

(1) n/2 is one of the factors of n

n/2 is a factor of n --> n/2 is an integer and from the pairs (1,2), (1,3) ... only 2 is divisible by 2
Hence , n = 2 --> (1) SUFFICIENT

(2) The lowest common multiple of n and n + 10 is an even number.

LCM (n,n+10) = EVEN

If n = 2 then LCM(2,12) = 12, which is EVEN
If n = 3 then LCM (3,13) = 39, which is ODD
Except for n=2, Like n=3, n = 5,7,11 .... LCM (n,n+10) will be ALWAYS ODD.
Hence, n = 2 --> (2) SUFFICIENT

_________________

KUDOS is the good manner to help the entire community.

Senior Manager
Status: Final Lap
Joined: 25 Oct 2012
Posts: 286
Concentration: General Management, Entrepreneurship
GPA: 3.54
WE: Project Management (Retail Banking)
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

26 Mar 2013, 03:57
2
KUDOS
3. If 0 < x < y and x and y are consecutive perfect squares, what is the remainder when y is divided by x?

(1) Both x and y is have 3 positive factors.
(2) Both $$\sqrt{x}$$ and $$\sqrt{y}$$ are prime numbers

(1) Both x and y is have 3 positive factors.

Consecutive perfect squares could be : 4 , 9 , 16 , 25 , 36 , 49 , 64 ....
Among these numbers, only 4 and 9 are consecutive perfect squares that have 3 positive factors ( for instance 16 = 4*4 = 2*2*2*2 --> 5 factors and SO ON )
Hence, y=9 and x=4 --> 9 = 4.2 +1 --> R = 1

Thus, (1) SUFFICIENT

(2) Both $$\sqrt{x}$$ and $$\sqrt{y}$$ are prime numbers
Consecutive perfect squares could be : 4 , 9 , 16 , 25 , 36 , 49 , 64 ....
Among these numbers, only 4 and 9 are consecutive perfect squares that have their square roots as prime numbers ( for example : $$\sqrt{16}$$ = 4, which is not a prime number and SO ON )
Hence, y=9 and x=4 --> 9 = 4.2 --> R = 1

Thus, (2) SUFFICIENT

_________________

KUDOS is the good manner to help the entire community.

Last edited by Rock750 on 29 Mar 2013, 04:20, edited 1 time in total.
Senior Manager
Status: Final Lap
Joined: 25 Oct 2012
Posts: 286
Concentration: General Management, Entrepreneurship
GPA: 3.54
WE: Project Management (Retail Banking)
Re: New Set: Number Properties!!! [#permalink]

### Show Tags

26 Mar 2013, 04:27
1
KUDOS
4. Each digit of the three-digit integer N is a multiple of 4, what is the value of K?

(1) The units digit of K is the least common multiple of the tens and hundreds digit of K
(2) K is NOT a multiple of 3.

Given that each digit of the three-digit integer N is a multiple of 4 , K could be : 444 or 448 or 484 or 488 ...

(1) The units digit of K is the least common multiple of the tens and hundreds digit of K

So , K should b equal to 444 (LCM(4,4) = 4) OR equalt to 888 (LCM(8,8) = 8) OR equalt to 488 (LCM(4,8) = 8) ....
Hence, (1) NOT SUFFICIENT

(2) K is NOT a multiple of 3.

So, K could be equal to 448 or 484 ...
Hence, (2) NOT SUFFICIENT

(1) + (2)

Both 488 and 848 have their units digit as the LCM of the tens and hundreds and are not a mulitple of 3
Hence, (1) + (2) NOT SUFFICIENT

_________________

KUDOS is the good manner to help the entire community.

Re: New Set: Number Properties!!!   [#permalink] 26 Mar 2013, 04:27

Go to page    1   2   3   4   5   6   7   8   9   10    Next  [ 183 posts ]

Similar topics Replies Last post
Similar
Topics:
4 When one new number is included in an existing set of 6 numbers 4 29 Mar 2016, 19:35
20 K is a set of numbers such that 15 06 May 2017, 10:36
290 New DS set!!! 138 30 Apr 2017, 23:24
4 If S is an infinite set of real numbers, is there a number 13 13 Aug 2011, 08:39
1 The set S of numbers has the following properties 6 09 Jun 2010, 11:10
Display posts from previous: Sort by