Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 24 May 2013, 07:09

# if n and k are positive integers, is sqrt. of

Author Message
TAGS:
Manager
Joined: 05 Jul 2006
Posts: 200
Followers: 1

Kudos [?]: 1 [0], given: 0

if n and k are positive integers, is sqrt. of [#permalink]  10 Sep 2006, 12:03
00:00

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
if n and k are positive integers, is sqrt. of (n+k)>2sqrt.of n?

k>3n
n+k>3n
Senior Manager
Joined: 14 Jul 2005
Posts: 410
Followers: 1

Kudos [?]: 3 [0], given: 0

Re: DS- n & k [#permalink]  10 Sep 2006, 12:46
lan583 wrote:
if n and k are positive integers, is sqrt. of (n+k)>2sqrt.of n?

k>3n
n+k>3n

A should be it...

From 1, k > 3n, adding n to both sides
k+n > 3n+n
k+n>4n

Taking sqrt, sqrt(k+n) > 2sqrt(n)
SUFF

From 2, n+k>3n, taking sqrt, sqrt(n+k) > sqrt(3n) which is INSUFF since
sqrt(3n) < sqrt(n+k) < 2*sqrt(n)
SVP
Joined: 05 Jul 2006
Posts: 1565
Followers: 4

Kudos [?]: 63 [0], given: 35

if n and k are positive integers, is sqrt. of (n+k)>2sqrt.of n?

1)k>3n
2) n+k>3n

square both sides

n+k>4n.....ie k>3n

from one ...needless to say anything......suff

from two

k>2n we can never deduct that k>3n....insuff

Similar topics Replies Last post
Similar
Topics:
If sqrt(n) is a positive integer, what is the value of n? 4 16 Jan 2005, 16:49
If n is a positive integer, is n equal to 100? (1) SQRT(n) 3 11 Dec 2005, 11:36
if n is a positive integer, is n equal to 100? 1) sqrt n 8 28 Dec 2005, 08:07
If n and k are positive integers, is sqrt(n+k) > 2 25 Jun 2007, 13:23
1 The positive integer n is divisible by 16. If sqrt(n) is 2 06 Mar 2013, 12:28
Display posts from previous: Sort by