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If x, y, and z are integers and (2^x)*(5^y)*z = 0.00064, what is the
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06 Nov 2014, 08:18
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68% (02:07) correct 32% (02:04) wrong based on 309 sessions
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Re: If x, y, and z are integers and (2^x)*(5^y)*z = 0.00064, what is the
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06 Nov 2014, 12:24
Statement 1 can be simplified to achieve 2^x*5^y*z=2*5^(5) if z=2^2*5 then 2^x*5^y = 2^1*5^4 From this we see x=1, 5=4, thus we can find xy.
Statement 2 is not enough as value of y would depend on value of z which is still unkown. 5^y*z=2^2*5^5. Insufficient to find answer



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Re: If x, y, and z are integers and (2^x)*(5^y)*z = 0.00064, what is the
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06 Nov 2014, 18:59
2^x*5^y*z= 64 * 10^5 = 2^6*2^5*5^5 = 2^1*5^5
Statement 1 : z = 20 We can write 2^1*5^5 = 2^1*5^6 *2^2*5^1 = 2^1*5^6*20 Since z =20, then x = 1 and y=6 Sufficient
Statement 2: x = –1 Since we don't know the value of z, we cannot determine the value of 5^y. Therefore, Statement 2 is insufficient
Answer should be A



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Re: If x, y, and z are integers and (2^x)*(5^y)*z = 0.00064, what is the
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06 Nov 2014, 21:55
2^x 5^y z = .00064 statement 1  z=20 clearly sufficient. statement 2  x=1 5^y * z = 128/10^5 5^y * z = 2^2 5^5 y=5 and x= 1 xy=5. sufficient. OA is D. Bunuel, please confirm.
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Re: If x, y, and z are integers and (2^x)*(5^y)*z = 0.00064, what is the
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19 Dec 2014, 04:18
If x, y, and z are integers and (2^x)*(5^y)*z = 0.00064, what is the value of xy? (1) z = 20 (2) x = –1 Here is my version. 1) if z=20 ==> 2^(x)*5^(y)=(0.00064/20)=0.000032 ==> 2^(x)*5^(y)=32*10^(6) ==> 2^(x)*5^(y)=2^(5)*(2*5)^(6) ==>x=1 and y=6 ==>xy=6 2) We know x=1 but nothing is said about z. Hence not sufficient. Hope it is clear
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Re: If x, y, and z are integers and (2^x)*(5^y)*z = 0.00064, what is the
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20 Dec 2014, 14:39
navkaran wrote: Statement 1 can be simplified to achieve 2^x*5^y*z=2*5^(5) if z=2^2*5 then 2^x*5^y = 2^1*5^4 From this we see x=1, 5=4, thus we can find xy.
Statement 2 is not enough as value of y would depend on value of z which is still unkown. 5^y*z=2^2*5^5. Insufficient to find answer Hi navkaran: Can you please elaborate how you go from "..if z=2^2*5" to "..then 2^x*5^y = 2^1*5^4". My reason is that I am getting a different value for y only, just want to make sure my methods aren't incorrect. Thank you.



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Re: If x, y, and z are integers and (2^x)*(5^y)*z = 0.00064, what is the
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14 Jan 2015, 20:39
The statement asks 2^x . 5^y. z = 0.00064 which can be translated into prime factors as
Statement 1: 2^x . 5^y. z = 2^6 . 10^ 6 = 2^0 . 5^ 6 comparing both the parts we get x= 0 & y=6 so xy= 0 sufficient.
Statement 2: 5^y . z = 0.000128 which means y & z can take any values. not sufficient.
Therefore A.



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Re: If x, y, and z are integers and (2^x)*(5^y)*z = 0.00064, what is the
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03 Mar 2017, 13:04
JusTLucK04 wrote: If x, y, and z are integers and 2x 5yz = 6.4 × 106, what is the value of xy? (1) z = 20 (2) x = 9 Posting solution for above problem.
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Re: If x, y, and z are integers and (2^x)*(5^y)*z = 0.00064, what is the
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04 Mar 2017, 05:24
(2^x)(5^y)z = 64 x 10^5 St 1: z = 20. therefore (2^x)(5^y) = 32 x 10^6 = 2^5 x (5 x 2)^6 = 2^1 x 5^6. Hence, x = 1 and y = 6. xy = 6. ANSWER St 2: x = 9. no idea about z. INSUFFICIENT. Option A
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Re: If x, y, and z are integers and (2^x)*(5^y)*z = 0.00064, what is the
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30 Aug 2018, 22:24
Please someone explain Statement 2:
statement 2 
x=1 substitute x in the given equation. 2^1 * 5^y * z = 64* 10^5 5^y * z = 2^2 5^5
y=5 and x= 1
xy=5. sufficient.
why cannot the OA be D Bunuel nightblade354
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Re: If x, y, and z are integers and (2^x)*(5^y)*z = 0.00064, what is the
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30 Aug 2018, 22:43




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