BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

fraction and exponent question

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Newbie | Next Rank: 10 Posts
Posts: 2
Joined: Tue Jan 18, 2011 1:28 am
by Frances87 » Mon Feb 21, 2011 12:27 pm
Sorry if this question has already been posted before, but it came up on a practise test I took, and I am stuck as to how to solve it:

If (1/5)m(1/4)18 = 1/2(10)35, m?

a. 18
b. 17
c. 21
d. 35
e. 3

The answer is D
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
Master | Next Rank: 500 Posts
Posts: 139
Joined: Fri Nov 26, 2010 4:45 pmFollowed by: 1 member
Location: Boston
Thanked: 20 times
GMAT Score:720

by stormier » Mon Feb 21, 2011 1:05 pm
Frances87 wrote:Sorry if this question has already been posted before, but it came up on a practise test I took, and I am stuck as to how to solve it:

If (1/5)m(1/4)18 = 1/2(10)35, m?

a. 18
b. 17
c. 21
d. 35
e. 3

The answer is D
(1/5)^m (1/4)^18 = 1/[2(10)^35]

=> 5^(-m)*2^(-36) = 2^(-1)*(10)^(-35)
=> 5^(-m)*2^(-36) = 2^(-1)*5^(-35)*2^(-35)
=> 5^(-m)*2^(-36) = 5^(-35)*2^(-36)

Thus -m = -35; or m=35
__________________________

please write a raised to power b as -> a^b

1/a^x = (1/a)^x = a^(-x)
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Senior | Next Rank: 100 Posts
Posts: 74
Joined: Fri Dec 17, 2010 12:37 pm
Location: Munich
Thanked: 3 times

by garuhape » Mon Feb 21, 2011 3:22 pm
Stomier,

can you please explain the general rule behind switching 4^18 to 2^36

Thx
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Senior | Next Rank: 100 Posts
Posts: 74
Joined: Fri Dec 17, 2010 12:37 pm
Location: Munich
Thanked: 3 times

by garuhape » Mon Feb 21, 2011 3:24 pm
garuhape wrote:Stomier,

can you please explain the general rule behind switching 4^18 to 2^36

Thx
I got it ;)

4*4 = 4^2 = 2*2*2*2 = 2^4
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 139
Joined: Fri Nov 26, 2010 4:45 pmFollowed by: 1 member
Location: Boston
Thanked: 20 times
GMAT Score:720

by stormier » Mon Feb 21, 2011 3:34 pm
garuhape wrote:
garuhape wrote:Stomier,

can you please explain the general rule behind switching 4^18 to 2^36

Thx
I got it ;)

4*4 = 4^2 = 2*2*2*2 = 2^4

(a^b)^c = a^(bc)

4^18 = (2^2)^18 = 2^(18*2) = 2^36


However,

a^(b^c) is not equal to a^bc
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Newbie | Next Rank: 10 Posts
Posts: 2
Joined: Tue Jan 18, 2011 1:28 am

by Frances87 » Tue Feb 22, 2011 3:27 am
Thanks Stormier, great explanation!
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1