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silverflamein
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Option Esilverflamein wrote:Is b the median of the three numbers a, b and c ??
1) a x c = b
2) a+c=b
Median
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neelgandham
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Anil Gandham
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1) For the option 1 - this doesn't provide any additional information as we can have several different options.
a1 = 2
c1 = -1
b1 = -5
(isn't a median)
Or
a2 = 2
c2 = 1/2
b2 = 1
(is a median)
2) Same here, doesn't provide any info alone, for a=2 and c=-2 b=0 (is median), and for the a=2, c=2 b=4 - isn't a median.
Combined together, you can deduce c = b-a from (2), then from (1) ba - a*a = b, therefore b=a*a/(a-1) and c = a / (a-1)
So, for (1) and (2) combined you have:
a, a*a/(a-1), a(a-1)
which depends on a
For a=2 you have 2, 4, 2 - b isn't a median
For a=1/2 1/2, 1/2, 1 - b is a median
Therefore, the answer is E
a1 = 2
c1 = -1
b1 = -5
(isn't a median)
Or
a2 = 2
c2 = 1/2
b2 = 1
(is a median)
2) Same here, doesn't provide any info alone, for a=2 and c=-2 b=0 (is median), and for the a=2, c=2 b=4 - isn't a median.
Combined together, you can deduce c = b-a from (2), then from (1) ba - a*a = b, therefore b=a*a/(a-1) and c = a / (a-1)
So, for (1) and (2) combined you have:
a, a*a/(a-1), a(a-1)
which depends on a
For a=2 you have 2, 4, 2 - b isn't a median
For a=1/2 1/2, 1/2, 1 - b is a median
Therefore, the answer is E
