gmatt1476 wrote:
Each entry in the multiplication table above is an integer that is either positive, negative, or zero. What is the value of a ?
(1) h ≠ 0
(2) c = f
DS95850.01
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First, the significance of multiplication table needs to be understood.
This is like a 3*3 matrix and results in the following products ,
a^2 = d
a*b = e
a*c = f
a*b = e
b^2 = g
b*c = h
c*a = f
c*b = h
c^2 = j
Now statement 1 says ,
h is not equal to 0.
That means neither b nor c equals zero as b*c = h;
But we cant tell anything about a.
Statement 2 says , c =f
a*c = f
a*c = c
c*(a-1) = 0
Now a can be equal to 1 or c can be equal to 0 .
So a can be equal to 1 or a may not be equal to 1 .
Not sufficient.
Together ,
c *(a-1) = 0
From statement h not equal to zero means c is not equal to zero.
If c is not equal to zero then (a-1) = 0 ( As we can divide the zero by c which is a non zero quantity )
Hence , a = 1
So option C is the answer.
Please give me KUDO s if you liked my explanation.
GMATNinja VeritasKarishma