Answer
The person's acceleration is $0.82~m/s^2$ downward.
Work Step by Step
We can find the person's mass:
$mg = 600~N$
$m = \frac{600~N}{9.80~m/s^2}$
$m = 61.2~kg$
Since the person's weight in the elevator is less than the person's weight on the ground, the person must be accelerating downward.
Let $F_N$ be the upward force exerted on the person by the elevator. Note that $F_N = 550~N$. We can find the person's acceleration:
$\sum F = ma$
$mg-F_N = ma$
$a = \frac{mg-F_N}{m}$
$a = \frac{600~N-550~N}{61.2~kg}$
$a = 0.82~m/s^2$
The person's acceleration is $0.82~m/s^2$ downward.
