If m, n and p are digits and their product is a digit, what is value

Question

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

Kurtosis · Answer

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

AMahmoodi · Answer

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.

PK32 · Answer

Answer will be E because for "P" we have two values 1 & -1 by combining two given equations

satyadeepkaw · Answer

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

Harambe · Answer

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

sobby · Answer

answer will be C..
Digit(0-9)...
1.MN=8--------1 , we can have p =0 or 1,mnp=8 or mnp= 0
2.m=2n, n=2p
m=4p-----2
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

akhiparth · Answer

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

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chetan2u · Answer

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

akhiparth · Answer

Answer will be C... Difference between digit & integer applies here

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suchita2409 · Answer

If m, n, and p are digits and their product is a digit, what is value of the product mnp?

(1) mn = 8
m*n=8, but nothing about p is given.
m*n*p depends on the value of p.
Insufficient.

(2) m = 2n and n = 2p
We here do have a relation between m,n and p .But still have no value for either m,n,or p .So Insufficient.

1+2
We have a relation and value of m*n .So,m*n*p could be deduced.
C it is.

If m, n and p are digits and their product is a digit, what is value

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