We have a group of three equations in three unknowns.
2x + 3y + z = 55,
x+ z- y = 4
and y - x + z = 12
Adding the second and third equations together, we get 2z = 16 or z = 8
Adding the first equation and twice the third equation, we get (2x + 3y + z) + 2*(y-x+z) = 55 + 2*12 = 79
Hence, 5y + 3z = 79.
As z=8, it implies that 5y = 55 or y=11
As this is not given in any of the options, the correct answer is option (e)
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