I had one question that I don't seem to understand.
Algebra: [(1/5)^m] * [(1/4)^18] = 1/[2(10)^35]
what is m?
Any insight would be appreciated, thanks.
Math Question
This topic has expert replies
- aim-wsc
- Legendary Member
- Posts: 2469
- Joined: Thu Apr 20, 2006 12:09 pm
- Location: BtG Underground
- Thanked: 85 times
- Followed by:14 members
...err can you make some things clear?
like: 2(10)^35 did you mean [(2(10))^35]=20^35
or 2 X (10)^35
OK i presume its latter one.
Its a tricky one & i must confess i had to used my instincts
before i explain the answer, you must understand the following rule
given n>m
then
(a^m) X (b^n) = ((aXb)^m) X (b^(n-m))
eg. (5^4) X (3^6) = ((5X3)^4) X (3^2)
= (15 ^4) X 9
OK back to problem.
LHS:
(1/5)^m * (1/4)^18
this can be also wirtten as
:arrow: (1/5)^m * (1/2)^36
RHS:
1/[2 X 10^35]= 1/[2 X (2X5)^35)]
:arrow: =1/[(2^36) X (5^35)]
ANSWER:
therefore
m=35
like: 2(10)^35 did you mean [(2(10))^35]=20^35
or 2 X (10)^35
OK i presume its latter one.
Its a tricky one & i must confess i had to used my instincts
before i explain the answer, you must understand the following rule
given n>m
then
(a^m) X (b^n) = ((aXb)^m) X (b^(n-m))
eg. (5^4) X (3^6) = ((5X3)^4) X (3^2)
= (15 ^4) X 9
OK back to problem.
LHS:
(1/5)^m * (1/4)^18
this can be also wirtten as
:arrow: (1/5)^m * (1/2)^36
RHS:
1/[2 X 10^35]= 1/[2 X (2X5)^35)]
:arrow: =1/[(2^36) X (5^35)]
ANSWER:
therefore
m=35
Getting started @BTG?
Beginner's Guide to GMAT | Beating GMAT & beyond
Please do not PM me, (not active anymore) contact Eric.
Beginner's Guide to GMAT | Beating GMAT & beyond
Please do not PM me, (not active anymore) contact Eric.
GMAT/MBA Expert
- beatthegmat
- Site Admin
- Posts: 6773
- Joined: Mon Feb 13, 2006 8:30 am
- Location: Los Angeles, CA
- Thanked: 1249 times
- Followed by:994 members
Check out page 48 of my GMAT Flashcards: https://www.beatthegmat.com/viewtopic.php?t=32kashewman wrote:Does anyone have a good formula for mixture problems? Thanks.
Beat The GMAT | The MBA Social Network
Community Management Team
Research Top GMAT Prep Courses:
https://www.beatthegmat.com/gmat-prep-courses
Research The World's Top MBA Programs:
https://www.beatthegmat.com/mba/school
Community Management Team
Research Top GMAT Prep Courses:
https://www.beatthegmat.com/gmat-prep-courses
Research The World's Top MBA Programs:
https://www.beatthegmat.com/mba/school