Integer Problem
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- ikaplan
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Two scenarios should be considered for this problem:
First scenario: x=2, y=3 and z=4 (so you have two even and one odd number)
Second scenario: x=1, y=2 and z=3 (the sequence contains two odd and one even number)
For (x+y)(y+z) both scenarios result in an odd integer.
First scenario: x=2, y=3 and z=4 (so you have two even and one odd number)
Second scenario: x=1, y=2 and z=3 (the sequence contains two odd and one even number)
For (x+y)(y+z) both scenarios result in an odd integer.
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yes, and C is not correct, because even*odd+even gives even
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- rishab1988
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Here is my approach
I used 3 different values of x,y, and z.There is no point in continuing further because these are 3 consecutive integers and after this the pattern (of odds and evens will repeat).
x y z xyz x+y+z xy+z (x+y)z (x+y)(y+z)
1 2 3 6 6 5 (Eliminate A and B)
2 3 4 10 20 35 (Eliminate C and D)
3 4 5
Therefore, by the principal of elimination the answer is E
I used 3 different values of x,y, and z.There is no point in continuing further because these are 3 consecutive integers and after this the pattern (of odds and evens will repeat).
x y z xyz x+y+z xy+z (x+y)z (x+y)(y+z)
1 2 3 6 6 5 (Eliminate A and B)
2 3 4 10 20 35 (Eliminate C and D)
3 4 5
Therefore, by the principal of elimination the answer is E