Final answer:
The range (possible values) of the random variable x in the voice communications system with 60 lines is from 0 to 60.
Step-by-step explanation:
The random variable, x, represents the number of lines in use at a particular time in a voice communications system with 60 lines. To determine the range (possible values) of x, we need to consider the minimum and maximum number of lines that could be in use. The minimum value of x is 0, which represents no lines in use. The maximum value of x is 60, which represents all 60 lines in use.