Given,
Probability of ith buffer getting full = $\large p(i) = \frac{1}{562}(33-i)$
Probability of all even number of buffers are full is $P(A)$
$P(A) =$$\large \sum_{i = 0,2,4,6,8,..,32} p(i) = \sum_{i = 0}^{16} p(2i)$
$P(A) =$ $\large \frac{1}{562} \left ( 33 + 31 + 29 + 27 + ....+ 1 \right )$
$P(A) =$$\frac{1}{562}\times 289 = 0.51423$