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If m is a positive integer, then m^3 has how many digits? [#permalink]
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20 Feb 2014, 01:17
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Re: If m is a positive integer, then m^3 has how many digits? [#permalink]
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20 Feb 2014, 01:17



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Re: If m is a positive integer, then m^3 has how many digits? [#permalink]
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20 Feb 2014, 01:31
Bunuel wrote: If m is a positive integer, then m^3 has how many digits?
(1) m has 3 digits. (2) m^2 has 5 digits.
Since the constraints are true for a range of values of m (between 100 and \([\sqrt{100000}]\), inclusive), this must be true for any m satisfying (1) and (2). Note that m=100 satisfies both. Since 100^3 has seven digits, m^3 must have seven digits.



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Re: If m is a positive integer, then m^3 has how many digits? [#permalink]
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21 Feb 2014, 00:20
Option E. From S1:Not suff since if m=100 ; m^3=7 digits And if m=900;m^3=9 digits.
From S2:m^2 has 5 digits=> 99<m<316 m=100;m^3=7 digits. m=315;m^3=8 digits.
Combining both the statements. m=3 digits and m^2=5 digits. Same situation as in case 2.Not suff.



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Re: If m is a positive integer, then m^3 has how many digits? [#permalink]
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21 Feb 2014, 06:39
Number Picking Strategy:
1)m can have three digits but m^3 differ e.g 100 and 999.Insufficient 2) m^2 can have 5 digits but m^3 differ e.g 100 and 315. Insufficient Together, the statements are insufficient. Take 100 and 315 as in the (2) above.
Answer E.



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Re: If m is a positive integer, then m^3 has how many digits? [#permalink]
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21 May 2014, 09:26
Hi Bunuel, Is this an odd ball? Or are there similar problems available? It took me 3:22 mins to solve it. I definitely need more practice. Thanks!
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Re: If m is a positive integer, then m^3 has how many digits? [#permalink]
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22 May 2014, 02:49



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Re: If m is a positive integer, then m^3 has how many digits? [#permalink]
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22 May 2014, 11:51
Oh Ok. Thanks for checking tho' Will take a look at the links you sent. Thanks again
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Re: If m is a positive integer, then m^3 has how many digits? [#permalink]
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23 May 2014, 04:02
Hi MensaNumber, I hope this helps, Statement 1:M has 3 digits M can be any number between 100 and 999, Number of digits in \(100^3\) = 7 Number of digits in \(1000^3\) = 10 => Hence \(999^3\) will have 9 digits So, number of digits could be 7, 8 or 9Statement 1 not sufficientStatement 2:\(M^2\) has 5 digits Smallest M is 100, where\(M^2\) has 5 digits Largest M would be close to 300, as \(300^2\) = 90000 M=100, will give number of digits in \(M^3\) as 7 M = 300, will give number of digits in \(M^3\) as 8 So, number of digits could be 7 or 8Statement 2 not sufficientCombining both statement, Number of digits could be 7 or 8Therefore, Answer: E
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Re: If m is a positive integer, then m^3 has how many digits? [#permalink]
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27 Nov 2017, 13:03
Hi All, We're told that M is a positive integer. We're asked for the number of digits that M^3 has. This question can be solved by TESTing VALUES. 1) M has 3 digits. IF.... M=100, then M^3 = 1,000,000 and the answer to the question is 7 M=300, then M^3 = 27,000,000 and the answer to the question is 8 Fact 1 is INSUFFICIENT 2) M^2 has 5 digits The same values that we used in Fact 1 also 'fit' Fact 2: M=100, M^2=10,000 and M^3 = 1,000,000 and the answer to the question is 7 M=300, M^2=90,000 and M^3 = 27,000,000 and the answer to the question is 8 Fact 2 is INSUFFICIENT Combined, there's no more work needed. We already have two values that 'fit' both Facts and produce two different answers. Combined, INSUFFICIENT Final Answer: GMAT assassins aren't born, they're made, Rich
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Re: If m is a positive integer, then m^3 has how many digits?
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