Chapter 9, Problem 49CRP

Explanation of Solution

Determine the time taken to retrieve a record from the middle of the file:

The total number of records in a file is 50,000 and the time required to interrogate an entry is 5 milliseconds.

• To find the record from the middle of the line, divide 50,000 records by 2 as given below:

$\begin{array}{c}\text{Middle}\text{record}=\frac{50,000}{2}\\ =25,000\end{array}$

• Thus, the number of records from the middle of a line is 25,000.
• To find the time taken to retrieve a record from the middle of a line, multiply 25,000 records by 5 milliseconds as given below:

$\begin{array}{c}\text{Time}\text{taken}\text{to}\text{retrieve}\text{\&}\end{array}$