Final answer:
In a Unix-based system, the statement 'expr 5 / 2' assigns the result of the integer division of 5 by 2 to the variable z; thus, the value of z would be 2 as integer division truncates the decimal.
Step-by-step explanation:
The statement z = 'expr 5 / 2' appears to be from a scripting or programming context and is likely aimed at assigning a value to the variable z. In most Unix-based systems where expr is used for expression evaluation in shell scripts, this would evaluate the integer division of 5 by 2. Assuming that expr follows traditional integer division rules, the result would be 2, because integer division truncates the decimal part and only returns the integer quotient.