GMAT Problem Solving (PS) | Re: In the following sequence: [x, y, z, 5, 7, 16, 28] each number is equa

From the sequence it is clear that 5=x+y+z or x+y=5-z...........(1)
We only need the value of z

16=7+5+z; hence, z=4

Substituting value of z in (1), x+y = 1

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