Assume we have a demand-paged memory. The page table is held in registers. It takes 9 milliseconds to service a page fau

[answerhappygod]

Assume we have a demand-paged memory. The page table is held in
registers. It takes 9 milliseconds to service a page fault if an
empty page is available or the replaced page is not modified, and
30 milliseconds if the replaced page is modified. Memory access
time is 100 nanoseconds. Assume that the page to be replaced is
modified 80 percent of the time. What is the maximum acceptable
page-fault rate for an effective access time of no more than 150
nanoseconds?