a + b = d and a b c = 0

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a + b = d and a b c = 0

by sanju09 » Fri Jun 18, 2010 4:17 am
a, b, c and d are numbers of different values such that
a + b = d and
a b c = 0
Which of the four numbers MUST be equal to zero?
(A) a
(B) b
(C) c
(D) d
(E) none
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by kvcpk » Fri Jun 18, 2010 4:21 am
sanju09 wrote:a, b, c and d are numbers of different values such that
a + b = d and
a b c = 0
Which of the four numbers MUST be equal to zero?
(A) a
(B) b
(C) c
(D) d
(E) none
given that all 4 are different..

so if a+b = d, then a or b cannot be zero..
if abc = 0 and a,b not equal to zero means c=0

answer C

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by amising6 » Fri Jun 18, 2010 4:26 am
a, b, c and d are numbers of different values such that
a + b = d and
a b c = 0
Which of the four numbers MUST be equal to zero?
(A) a
(B) b
(C) c
(D) d
(E)

a+b=d
so we know all of them have different values a,b and d cannot be 0
as if a or b will be zero than value of d will be either equal to a or b (which is not possible)
and we know abc=0 so c will be zero
ans =c
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