The waiting time ?W for accessing one record from a computer database is a random variable...

The waiting time ?W for accessing one record from a computer database is a random variable uniformly distributed between 00 and 3232 milliseconds.

The read time ?R for moving the information from the disk to the main memory is 88 milliseconds.

The random variable ?X milliseconds is the total access time (waiting time + read time) to get one block of information from the disk.

Before performing a certain task, the computer must access 99 different blocks of information from the disk. (Access times for different blocks are independent of one another.)

The total access time for all the information is a random variable ?A milliseconds.

Compute the following:

- E[X]

- Var[X]

- Standard deviation of A

- P[A>243]

- P[A<192]

Expert Solution

orchestra answered 2 years ago

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