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

 It is currently 24 May 2013, 03:54

Is 5^k less than 1,000 ? (1) 5^(k-1) > 3,000 (2) 5^(k-1)

Author Message
TAGS:
Senior Manager
Joined: 22 Aug 2003
Posts: 262
Location: Bangalore
Followers: 1

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

Is 5^k less than 1,000 ? (1) 5^(k-1) > 3,000 (2) 5^(k-1) [#permalink]  06 Oct 2003, 02:08
00:00

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
20. Is 5^k less than 1,000 ?
(1) 5^(k-1) > 3,000
(2) 5^(k-1) = 5^k - 500
i din't like the official answer...
CEO
Joined: 15 Aug 2003
Posts: 3550
Followers: 55

Kudos [?]: 626 [0], given: 781

Re: DS: 5^k [#permalink]  06 Oct 2003, 02:54
Vicky wrote:
20. Is 5^k less than 1,000 ?
(1) 5^(k-1) > 3,000
(2) 5^(k-1) = 5^k - 500
i din't like the official answer...

1. 5^k > 15000 ..sufficient

2. 5^k = 2500/4 ...sufficient

D.

I get a NO with 1. and a YES with 2. this is unusual.. what did i miss?

thanks
praetorian

Yeah... the sets are mutually exclusive. A correct problem, if it has D as the right answer, gives the same answer in both cases.
Intern
Joined: 13 Sep 2003
Posts: 45
Location: US
Followers: 0

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

How did you get the 2. 5^k = 2500/4 ...sufficient ?
can you explain.

my reasoning from the second statement is

5^k-1 - 5^k = 1000....therefore 5^k can be any value...

not sure ...
Manager
Joined: 26 Aug 2003
Posts: 238
Location: United States
Followers: 1

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

Re: DS: 5^k [#permalink]  31 Oct 2003, 13:03
praetorian123 wrote:
Vicky wrote:
20. Is 5^k less than 1,000 ?
(1) 5^(k-1) > 3,000
(2) 5^(k-1) = 5^k - 500
i din't like the official answer...

1. 5^k > 15000 ..sufficient

2. 5^k = 2500/4 ...sufficient

D.

I get a NO with 1. and a YES with 2. this is unusual.. what did i miss?

thanks
praetorian

--------

sudzpwc wrote:
How did you get the 2. 5^k = 2500/4 ...sufficient ?
can you explain.

my reasoning from the second statement is

5^k-1 - 5^k = 1000....therefore 5^k can be any value...

not sure ...

How do you get 5^k-1 - 5^k = 1000? When it's clearly not possible when you look at the statement (2).
Intern
Joined: 30 Oct 2003
Posts: 34
Location: uk
Followers: 0

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

Sud,

if you replace 5^k with x,
then you can see that x/5 = x-500
=> x = 2500/4 =625=5^k
=>k=4
Senior Manager
Joined: 23 Sep 2003
Posts: 327
Location: US
Followers: 1

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

OR

5^k-1 = 5^k - 500
(5^k)/5 = 5^k - 500
5^k = 5(5^k - 500)
2500 = 5^k(5-1)
Intern
Joined: 09 Oct 2003
Posts: 29
Location: US
Followers: 0

Kudos [?]: 2 [0], given: 0

5^k-1 = 5^k - 500
(5^k)/5 = 5^k - 500
5^k = 5(5^k - 500)
2500 = 5^k(5-1)
Intern
Joined: 09 Oct 2003
Posts: 29
Location: US
Followers: 0

Kudos [?]: 2 [0], given: 0

5^k-1 = 5^k - 500
(5^k)/5 = 5^k - 500
5^k = 5(5^k - 500)
2500 = 5^k(5-1)

I guess so
Intern
Joined: 09 Oct 2003
Posts: 29
Location: US
Followers: 0

Kudos [?]: 2 [0], given: 0

Solve them [#permalink]  04 Nov 2003, 12:24
If x>0, x/50 + x/25 is what percent of x?

A. 6%
B. 25%
C. 37 1/2%
D. 60%
E. 75 %
Intern
Joined: 09 Oct 2003
Posts: 29
Location: US
Followers: 0

Kudos [?]: 2 [0], given: 0

If x>0, x/50 + x/25 is what percent of x?

A. 6%
B. 25%
C. 37 1/2%
D. 60%
E. 75 %
Intern
Joined: 09 Oct 2003
Posts: 29
Location: US
Followers: 0

Kudos [?]: 2 [0], given: 0

This is the Question from GMAT Paper Test Series
Similar topics Replies Last post
Similar
Topics:
Is 5^k less than 1,000? (1) 5^(k-1) > 3000 (2) 5^(k-1) = 4 12 Dec 2003, 16:07
Is 5^k less than 1,000 ? (1) 5^k-1 > 3000 (2) 5^k-1 = 5^k 2 11 Jul 2004, 12:09
DS... is 5^k less than 1000? 1) 5^(k+1) > 3000 2) 5^(k-1) 4 24 Jul 2005, 10:24
Is 5^k less than 1,000 ? (1) 5^(k-1) > 3000 (2) 5^(k-1) = 2 28 Feb 2007, 22:49
Is 5^k less than 1,000? (1) 5^k+1 > 3000 (2) 5^K-1 = 5^K 4 15 Mar 2007, 13:09
Display posts from previous: Sort by