1/5)^m (1/4)^18 = 1/2(10)^35
(1/5^m) (1/2^2)18=1/2(2*5)^35
(1/5^m) (1/2^36)=1/2*2^35*5^35
(1/5^m)=(1/5^35)
therefore m=35
Could someone please please please tell me step by step, how to go from here:
1/5^m) (1/2^36)=1/2*2^35*5^35
to here: (1/5^m)=(1/5^35)
driving me nutts
This topic has expert replies
- Stuart@KaplanGMAT
- GMAT Instructor
- Posts: 3225
- Joined: Tue Jan 08, 2008 2:40 pm
- Location: Toronto
- Thanked: 1710 times
- Followed by:614 members
- GMAT Score:800
Unless the question was misquoted, the reason you're going crazy is because there is no way to get that solution.cris wrote:1/5)^m (1/4)^18 = 1/2(10)^35
(1/5^m) (1/2^2)18=1/2(2*5)^35
(1/5^m) (1/2^36)=1/2*2^35*5^35
(1/5^m)=(1/5^35)
therefore m=35
Could someone please please please tell me step by step, how to go from here:
1/5^m) (1/2^36)=1/2*2^35*5^35
to here: (1/5^m)=(1/5^35)
(1/5)^m * (1/2)^36 = (1/2) * 2^35 * 5^35
(1/5)^m * (1/2)^36 = 2^34 * 5^35
(1/5)^m = (2^34 * 5^35)/(1/2)^36
(1/5)^m = (2^34 * 5^35) * 2^36
(1/5)^m = 2^70 * 5^35
5^(-m)/5^35 = 2^70
5^(-m-35) = 2^70
As you can see, there is no simple solution for m. If we backsolve with m=35, we get:
5^(-70) = 2^70
which clearly isn't true.
Does someone have the source of the question? Something must have been lost or transposed in the translation.
Stuart Kovinsky | Kaplan GMAT Faculty | Toronto
Kaplan Exclusive: The Official Test Day Experience | Ready to Take a Free Practice Test? | Kaplan/Beat the GMAT Member Discount
BTG100 for $100 off a full course
Thank god !! :)
Stuart, this question was posted by SALMA, Jan 29 2008 under the title "[b]Powers[/b]"....you can find it easly in the posts if you go a bit downwards....
Someone posted that solution and Slama said that is was ok....and I just couldnt see how...
Once again Stuart, thank you
Stuart, this question was posted by SALMA, Jan 29 2008 under the title "[b]Powers[/b]"....you can find it easly in the posts if you go a bit downwards....
Someone posted that solution and Slama said that is was ok....and I just couldnt see how...
Once again Stuart, thank you
- Stuart@KaplanGMAT
- GMAT Instructor
- Posts: 3225
- Joined: Tue Jan 08, 2008 2:40 pm
- Location: Toronto
- Thanked: 1710 times
- Followed by:614 members
- GMAT Score:800
Is the right side supposed to be:sibbineni wrote:I think the question is
(1/5)^m (1/4)^18 = 1/2(10)^35....
m=35 is the answer
Suggest me if iam wrong
1/(2*(10^35))?
If the whole expression is in the denominator, then the question makes sense.
We now have:
(1/5)^m * (1/2)^36 = 1/(2 * 2^35 * 5^35)
(1/5)^m * (1/2)^36 = 1/(2^36 * 5^35)
(1/5)^m * (1/2)^36 = (1/2)^36 * (1/5)^35
Dividing both sides by (1/2)^36, we get:
(1/5)^m = (1/5)^35
and therefore m=35
Last edited by Stuart@KaplanGMAT on Thu Jan 31, 2008 3:27 pm, edited 1 time in total.
Stuart Kovinsky | Kaplan GMAT Faculty | Toronto
Kaplan Exclusive: The Official Test Day Experience | Ready to Take a Free Practice Test? | Kaplan/Beat the GMAT Member Discount
BTG100 for $100 off a full course