Last visit was: 25 Apr 2024, 04:42 It is currently 25 Apr 2024, 04:42

Close
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Close
Request Expert Reply
Confirm Cancel
SORT BY:
Date
Math Expert
Joined: 02 Sep 2009
Posts: 92912
Own Kudos [?]: 618920 [68]
Given Kudos: 81595
Send PM
Most Helpful Reply
User avatar
Manager
Manager
Joined: 17 Mar 2015
Posts: 106
Own Kudos [?]: 211 [40]
Given Kudos: 4
Send PM
Math Expert
Joined: 02 Sep 2009
Posts: 92912
Own Kudos [?]: 618920 [7]
Given Kudos: 81595
Send PM
General Discussion
avatar
Intern
Intern
Joined: 01 Jan 2015
Posts: 16
Own Kudos [?]: 33 [5]
Given Kudos: 7
Send PM
Re: If 3^4/(2^3*5^6) is expressed as a terminating decimal, how many nonze [#permalink]
1
Kudos
3
Bookmarks
Bunuel wrote:
If \(\frac{3^4}{2^3*5^6}\) is expressed as a terminating decimal, how many nonzero digits will the decimal have?

A. One
B. Two
C. Three
D. Four
E. Six

Kudos for a correct solution.



\(\frac{81}{125*10^3} = \frac{0.648}{10^3}\)

Hence answer is C
avatar
Intern
Intern
Joined: 22 Aug 2014
Posts: 30
Own Kudos [?]: 37 [3]
Given Kudos: 6
Send PM
Re: If 3^4/(2^3*5^6) is expressed as a terminating decimal, how many nonze [#permalink]
2
Kudos
1
Bookmarks
Bunuel wrote:
If \(\frac{3^4}{2^3*5^6}\) is expressed as a terminating decimal, how many nonzero digits will the decimal have?

A. One
B. Two
C. Three
D. Four
E. Six

Kudos for a correct solution.


We have to find the count of non-zero nos in the expression 3^4/2^3*5^6

If you look at the nos in denominator, we can see that it is 2 and 5. 2*5 = 10 and this will not divide the fraction and give new nos.
Thus the eqn can be changed to

= 3^4 /5^3 * 10^3

= 81/125 (10^3 is not required as it does not alter the solution)

= 0.648

Thus, # non zero decimal nos is 3

Option C
avatar
Intern
Intern
Joined: 22 Mar 2015
Posts: 3
Own Kudos [?]: 5 [1]
Given Kudos: 2
Send PM
Re: If 3^4/(2^3*5^6) is expressed as a terminating decimal, how many nonze [#permalink]
1
Kudos
3^4/(2^3*5^6) = 3^4/(2^3*5^3*5^3) = 3^4/(10^3*5^3) = 10^-3 * 3^4/5^3 = 10^-3 * 81/125 ==> 10^-3 *0.625 ==> choose C.
Senior Manager
Senior Manager
Joined: 21 Jan 2015
Posts: 423
Own Kudos [?]: 356 [0]
Given Kudos: 82
Location: India
Concentration: Strategy, Marketing
GMAT 1: 620 Q48 V28
GMAT 2: 690 Q49 V35
WE:Sales (Consumer Products)
Send PM
Re: If 3^4/(2^3*5^6) is expressed as a terminating decimal, how many nonze [#permalink]
Bunuel wrote:
If \(\frac{3^4}{2^3*5^6}\) is expressed as a terminating decimal, how many nonzero digits will the decimal have?

A. One
B. Two
C. Three
D. Four
E. Six


Ans: C
Solution: given question has 3^4=81, 2^3*5^6= 10^3*5^3
now (81*10^-3)/5^3
which gives us 648 if we remove the decimal part for now.
as we know we need to find how many nonzero digits are there, three is the answer.
ans: C
avatar
Manager
Manager
Joined: 02 Mar 2012
Posts: 201
Own Kudos [?]: 292 [1]
Given Kudos: 4
Schools: Schulich '16
Send PM
Re: If 3^4/(2^3*5^6) is expressed as a terminating decimal, how many nonze [#permalink]
1
Kudos
C-three

81/(125∗10^3)=0.648/10^3

Hence answer is C
User avatar
Manager
Manager
Joined: 03 Oct 2013
Status:Kitchener
Posts: 64
Own Kudos [?]: 46 [1]
Given Kudos: 144
Location: Canada
Concentration: Finance, Finance
GPA: 2.9
WE:Education (Education)
Send PM
Re: If 3^4/(2^3*5^6) is expressed as a terminating decimal, how many nonze [#permalink]
1
Kudos
the answer is C
we can multiple the numerator and denominator by 2^3 to get the powers of 2 and 5 in the denominator are equal
so 3^4*2^3/2^6*5^6= 81*8/10^6 =648/10^6
Senior Manager
Senior Manager
Joined: 23 Jan 2013
Posts: 429
Own Kudos [?]: 263 [0]
Given Kudos: 43
Schools: Cambridge'16
Re: If 3^4/(2^3*5^6) is expressed as a terminating decimal, how many nonze [#permalink]
was stuck but it is clear that A and B out

guessed C
avatar
Manager
Manager
Joined: 09 Jan 2013
Posts: 55
Own Kudos [?]: 352 [3]
Given Kudos: 185
Concentration: Entrepreneurship, Sustainability
GMAT 1: 650 Q45 V34
GMAT 2: 740 Q51 V39
GRE 1: Q790 V650
GPA: 3.76
WE:Other (Pharmaceuticals and Biotech)
Send PM
Re: If 3^4/(2^3*5^6) is expressed as a terminating decimal, how many nonze [#permalink]
3
Kudos
Just convert the denominator into power of 10. You don't really need to do any calculation

\(\frac{3^4}{2^3*5^6} = \frac{3^4*2^3}{10^6} = \frac{81*8}{10^6}\)

81*8 is clearly a 3 digit no.

Answer C.
avatar
Intern
Intern
Joined: 09 Oct 2011
Posts: 18
Own Kudos [?]: 76 [1]
Given Kudos: 9
Send PM
Re: If 3^4/(2^3*5^6) is expressed as a terminating decimal, how many nonze [#permalink]
1
Kudos
Let 's understand the concept of terminating decimal

terminating decimal = 1/ 2 power a * 1/ 5 power of b ( concept )

Now multiply by 2 to the power of 3 with Numerator and denominator to convert terminating decimal .

Now exponent concept - 2to the power 6 and 5 to the power 6 = 10 to the power 6


Now original fraction became

648/ 1000000 = .000648

Hence After decimal there are 3 Non zeros .

Answer c
Intern
Intern
Joined: 23 Apr 2014
Posts: 45
Own Kudos [?]: 24 [0]
Given Kudos: 82
Location: United States
GMAT 1: 680 Q50 V31
GPA: 2.75
Send PM
Re: If 3^4/(2^3*5^6) is expressed as a terminating decimal, how many nonze [#permalink]
Bunuel wrote:
If \(\frac{3^4}{2^3*5^6}\) is expressed as a terminating decimal, how many nonzero digits will the decimal have?

A. One
B. Two
C. Three
D. Four
E. Six

Kudos for a correct solution.



Denominator has powers of 2 and 5, so this gives hint that there is power of 10 actually in denominator. Segregating powers of 10 will help in final division.
Denominator:- 2^3 * 5^6 = (2^3 * 5^3) * 5^3 = 10^3 * 125
So final value is 81/1000*125

Now 1000 in denominator will not add to non-zero value of final answer
So 3^4/(2^3*5^6) = 10^-3 * (81/125)
This final division gives us 3 non-zero digits.

In questions which asks us to find such non-zero digits , we can simply segregate common powers of 2 and 5 from denominator as they lead to zeroes after division.

Hope this helps.
Intern
Intern
Joined: 08 Sep 2016
Posts: 26
Own Kudos [?]: 23 [0]
Given Kudos: 119
Send PM
Re: If 3^4/(2^3*5^6) is expressed as a terminating decimal, how many nonze [#permalink]
@Bunnel,

This might be really basic but i am unable to understand why the numerator and denominator are multiplied by 2^3?

Please explain. what am i missing?

Thanks in Advance!
S
Math Expert
Joined: 02 Sep 2009
Posts: 92912
Own Kudos [?]: 618920 [0]
Given Kudos: 81595
Send PM
Re: If 3^4/(2^3*5^6) is expressed as a terminating decimal, how many nonze [#permalink]
Expert Reply
shinrai15 wrote:
@Bunnel,

This might be really basic but i am unable to understand why the numerator and denominator are multiplied by 2^3?

Please explain. what am i missing?

Thanks in Advance!
S


We need to multiply by 2^3/2^3 in order to convert the denominator to the base of 10 and then to convert the fraction into the decimal form: 0.xxxx.
Intern
Intern
Joined: 15 Aug 2017
Posts: 43
Own Kudos [?]: 9 [0]
Given Kudos: 277
Location: India
Schools: HBS '22
Send PM
Re: If 3^4/(2^3*5^6) is expressed as a terminating decimal, how many nonze [#permalink]
Bunuel wrote:
If \(\frac{3^4}{2^3*5^6}\) is expressed as a terminating decimal, how many nonzero digits will the decimal have?

A. One
B. Two
C. Three
D. Four
E. Six

Kudos for a correct solution.


10 can be created in the above equation by 2*5 only. Since we've only three 2's, we can create a max of three 10's. Hence 3 zeros.

However, I'm not sure if this logic is right. Comments?
User avatar
Non-Human User
Joined: 09 Sep 2013
Posts: 32667
Own Kudos [?]: 821 [0]
Given Kudos: 0
Send PM
Re: If 3^4/(2^3*5^6) is expressed as a terminating decimal, how many nonze [#permalink]
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
GMAT Club Bot
Re: If 3^4/(2^3*5^6) is expressed as a terminating decimal, how many nonze [#permalink]
Moderators:
Math Expert
92912 posts
Senior Moderator - Masters Forum
3137 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne