Carcass wrote:
In the sequence x, y, z, 57, when any one of the first three terms is subtracted from the term immediately following it, the result equals x + 3. What is the value of x?
(A) 9
(B) 10
(C) 11
(D) 12
(E) 13
(x + 3) = (y - x) = (z - y) = (57 - z)
From 1st and 2nd terms;
x + 3 = y - x
y = 2x + 3
From 1st and 3rd terms;
x + 3 = z - y
z = x + y + 3 = x + (2x + 3) + 3 = 3x + 6
From 1st and 4th terms;
x + 3 = 57 - z
x + 3 = 57 - (3x + 6)
4x = 48
x = 12
Hence, option D