Decide whether a discrete or continuous random variable is the best model for each of the following variables:
(a) The number of cracks exceeding one-half inch in 10 miles of an interstate highway.
(b) The weight of an injection-molded plastic part.
(c) The number of molecules in a sample of gas.
(d) The concentration of output from a reactor.
(e) The current in an electronic circuit.
Step 1 of 6:
In this problem we have to decide the given variables are continuous or discrete random variables.
Discrete random variable: a discrete random variable is a variable, which can only take a countable number of values.
continuous random variable: a continuous random variable is a variable whose value is obtained by measuring.