Target Test Prep 20% Off Flash Sale is on! Code: FLASH20

Redeem
Target Test Prep Flash Sale
Target Test Prep is 20% off right now!
Use code FLASH20

Available with Beat the GMAT members only code

MORE DETAILS
Magoosh
Magoosh
Study with Magoosh GMAT prep

Available with Beat the GMAT members only code

MORE DETAILS
Magoosh

Powers

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Junior | Next Rank: 30 Posts
Posts: 29
Joined: Sat May 07, 2011 6:16 am

Powers

by vinayreguri » Sun Jun 12, 2011 6:23 am
Find the value of (5^(5x+1)-5^(5x-1)+24)/(2.4*5^5x+12)
Top
Legendary Member
Posts: 1448
Joined: Tue May 17, 2011 9:55 am
Location: India
Thanked: 375 times
Followed by:53 members

by Frankenstein » Sun Jun 12, 2011 6:40 am
Hi,
(5^(5x+1)-5^(5x-1)+24)/(2.4*5^5x+12) = (5^2*5^(5x-1)-5^(5x-1)+24)/(2.4*(5^5x+5))
= ((5^2-1)*5^(5x-1)+24)/(2.4*5*(5^(5x-1) + 1)) = (24*(5^(5x-1) +1)/(12*(5^(5x-1) + 1)) = 2
Cheers!

Things are not what they appear to be... nor are they otherwise
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 » Sun Jun 12, 2011 6:59 am
vinayreguri wrote:Find the value of (5^(5x+1)-5^(5x-1)+24)/(2.4*5^5x+12)
(5^(5x + 1) = (5^5x)*(5^1) = 5*(5^5x)
(5^(5x - 1) = (5^5x)*(5^-1) = (5^5x)*(1/5) = 0.2*(5^5x)

... (5^(5x + 1) - 5^(5x - 1) + 24)/(2.4*5^5x + 12)
= (5*(5^5x) - 5*(5^5x) + 24)/(2.4*5^5x + 12)
= [(5 - 0.2)*(5^5x) + 24]/[2.4*(5^5x) + 12]
= [4.8*(5^5x) + 24]/[2.4*(5^5x) + 12]
= 2*[2.4*(5^5x) + 12]/[2.4*(5^5x) + 12]
= 2
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
Junior | Next Rank: 30 Posts
Posts: 29
Joined: Sat May 07, 2011 6:16 am

by vinayreguri » Sun Jun 12, 2011 7:13 am
Anurag@Gurome

is this a level 650+ Q
Top
Master | Next Rank: 500 Posts
Posts: 112
Joined: Sun Jun 13, 2010 9:20 am
Thanked: 5 times
GMAT Score:640

by sunilrawat » Sun Jun 12, 2011 7:17 am
(5^(5x+1)-5^(5x-1)+24)/(2.4*5^5x+12)
= (5^5x(5-1/5)+24)/(12(2/10*5^5x-1)+1)
= (24(5^5x-1+1))/(12(5^5x-1)+1)
= 2
Top
User avatar
Legendary Member
Posts: 1309
Joined: Mon Apr 04, 2011 5:34 am
Location: India
Thanked: 310 times
Followed by:123 members
GMAT Score:750

by cans » Tue Jun 14, 2011 4:04 am
(5^(5x+1)-5^(5x-1)+24)/(2.4*5^5x+12)
let 5^(5x)=a
then numerator 5a - (a/5) + 24 = 24(a+5)/5
denominator = 2.4a + 12 = 12(a+5)/5
thus numerator/denominator = 2
If my post helped you- let me know by pushing the thanks button ;)

Contact me about long distance tutoring!
[email protected]

Cans!!
Top
Post new topic Post Reply
• Page 1 of 1