Eva wants to collect a simple random sample.

Question

She uses a random number generator to select 5 people from a numbered list of 50 people.
It gives the following numbers:
18,25,67,13,45,89,02
a) Which two numbers could not be used to select the sample?
Eva needs an extra person for her sample. She uses the same number generator, which gives 25.
b) Why is 25 not useful for Eva?

Answer 1

a) The numbers 67 and 89 could not be used to select the sample because they are greater than the total number of people in the list (50).

b) 25 is not useful for Eva because she has already selected that number in her initial sample. In a simple random sample, each individual can only be selected once.