
Answer:
a) Discrete. Values 0,1,2,3,...,27
b) Continuous. Can be any real positive value.
Step-by-step explanation:
A random variable is discrete if it's values are natural, counting values. That is 0,1,2,3,4 etc
A random variable is continuous if it's values are real numbers, decimal. For example, 1, 2, 0.5, 0.22, etc.
(a) The number of people with blood type Upper A in a random sample of 27 people.
You cannot have 1.5 people with blood type Upper A, for example.
You can have 0,1,2,3,...,27.
This random variable is discrete.
(b) The square footage of a house.
This square footage can be any real positive value, so it is continuous.