binomial distribution: simple doubt

[revati]

Which of the following could never be described by a binomial distribution?
a) The number of defective widgets
produced by an assembly process.
c) The amount of water used daily by a
single household.
b) All of these could always be described by
a binomial distribution.
d) The number of people in your class
who can answer this question correctly.

[Aashna]

amount of water used daily by single household

[Dreyfus]

Well a sequence of i.i.d Bernoulli trials is what modeled as Binomial rv.
Now in option a) The number of defective widgets can modeled with binomial distribution as its really a sequence of i.i.d Bernoulli trials where each trial is whether a widget is defective or not!
Similarly in option d) as well number of people in the class who can actually solve this problem can be modeled with binomial distribution.
But in option c) the amount of water is a random variable but its domain is a set which is'nt a countable set. So it can never be characterized with binomial distribution.

[revati]

thanks a lot :)

[revati]

thanks aashna :)