Memory access time = 200 nsec
page-fault service time = 20 msec
EAT = (1 – p) × 200 + p (20 × 10^6) =
performance degradation < 10 %
without page fault access time= 200 nsec & with page fault=220 nsec
220=200 - 200p + 20,000,000p
p= 20/19999800 => p=0.000001