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If m, n and p are digits and their product is a digit, what is value
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19 Jan 2017, 08:05
Question Stats:
38% (01:39) correct 62% (01:40) wrong based on 162 sessions
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Re: If m, n and p are digits and their product is a digit, what is value
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19 Jan 2017, 09:40
mnp = ?
St1: mn = 8 > p can be 1 or 0. mnp = 8 or mnp = 0 Not Sufficient.
St2: m = 2n and n = 2p > mnp = 8(p^3) = 1 or 0. Not Sufficient.
Combining St1 and St2, mn = 8 > m or n cannot be 0 > Hence p cannot be 0 > mnp = 8. Sufficient.
Answer: C



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If m, n and p are digits and their product is a digit, what is value
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19 Jan 2017, 14:12
Hi,
mnp=?
st1: as it doesn't give us the value for P it is not sufficient. for ex for p=0 mnp=0, and for p=1, mnp=8.
st2: it doesn't reveal any real value for any of variables so it is not sufficient.
st1+st2: m=2n=2(2p)=4p & mn=8=4p*2p=8p^2 therefore we have p=+1 or 1 . for p=1, mnp=8 & for p=1 mnp=8 which is not sufficient. answer is E.



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Re: If m, n and p are digits and their product is a digit, what is value
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20 Jan 2017, 21:59
Answer will be E because for "P" we have two values 1 & 1 by combining two given equations



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Re: If m, n and p are digits and their product is a digit, what is value
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21 Jan 2017, 02:30
Since it is given that m,n and p are digits, they can assume either positive or negative value. Therefore E is the best answer



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Re: If m, n and p are digits and their product is a digit, what is value
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23 Jan 2017, 13:49
clearly statement 1 is insufficient. Statement 2 is also insufficient because it only gives information about 2 of the 3 variables.
Combining both statements: 2n*n=8>n=+/4, m=+/9, p=+/2. Since there is no indications of whether the numbers are positive or negative, we don't have enough information to answer the question.
Answer: E



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Re: If m, n and p are digits and their product is a digit, what is value
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23 Jan 2017, 20:47
Bunuel wrote: If m, n and p are digits and their product is a digit, what is value of the product mnp?
(1) mn = 8 (2) m = 2n and n = 2p answer will be C.. Digit(09)... 1.MN=81 , we can have p =0 or 1,mnp=8 or mnp= 0 2.m=2n, n=2p m=4p2 combining 1 and 2 m and n are not 0 from statement 1,so p cant be 0(from statement 2).. MNP=8. sufficient so c



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Re: If m, n and p are digits and their product is a digit, what is value
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23 Jan 2017, 22:16
Good to read various explanations... I also thought answer to be C but correct one is E... Forgot to take n square as + or  2 which makes two different answers when combined statements Sent from my Lenovo A7020a48 using GMAT Club Forum mobile app



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Re: If m, n and p are digits and their product is a digit, what is value
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23 Jan 2017, 22:29
Bunuel wrote: If m, n and p are digits and their product is a digit, what is value of the product mnp?
(1) mn = 8 (2) m = 2n and n = 2p Hi All those who have answered E will not be correct. Reason.. there are only 10 digits : 0 to 9 1 is a number made from digit 1.. 1) mn is 8.. If P is 0, mnp is 0.. If p is 1, mnp is 8.. Insufficient 2) m=2n and n = 2p.. mnp= 4p*2p*p=8p^3.. p could be 0or 1.. Combined.. If p is 0, n =2p=2*0=0.. If this is so mn will be 0 and not 8.. So p is not 0 but 1 and mnp is 8*1=8 Sufficient C
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Re: If m, n and p are digits and their product is a digit, what is value
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25 Jan 2017, 07:10
akhiparth wrote: Good to read various explanations... I also thought answer to be C but correct one is E... Forgot to take n square as + or  2 which makes two different answers when combined statements Sent from my Lenovo A7020a48 using GMAT Club Forum mobile appAnswer will be C... Difference between digit & integer applies here Sent from my Lenovo A7020a48 using GMAT Club Forum mobile app



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Re: If m, n and p are digits and their product is a digit, what is value
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06 Feb 2018, 11:36
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