1. a. The parents of every student at the school is posted a questionnaire to fill in.
This method would be expensive and take a lot of organising and many parents would not bother filling in the questionnaire or sending it back.
b. The parents of all Year 12 students at the school are asked to take part.
The views of the parents of Year 12 students could be quite different from the views of the parents of younger students.
c. A sample of 30 first year students are chosen at random.
This would be an unbiased way to choose parents of first year students but not the whole school.
d. The Principal invites parents to a meeting and the parents who turn up are asked their opinion.
Parents who have strong views would be more likely to attend and many parents may not be able to attend on a particular day.
e. The students' names are listed alphabetically and every 10th student is selected and their parents are sent a questionnaire.
This method is probably the best as the sample would be quite random and be representative of students from all levels of the school.
2.
a

A sample taken for a survey where every member of a population has an equal chance of being chosen is said to be a random sample. TRUE. 
b

A sample which does not accurately represent the group from which it is taken is called arandom sample. FALSE. 
c

A census involves surveying every member of a population. TRUE . 
d

If a sample is taken and it is not random, any conclusions are likely to be biased.TRUE. 
e

A census is held every three years in Australia and New Zealand. FALSE. 
f

The first 100 students to arrive at school are asked their opinions of the school! The results of this survey be likely to be biased. TRUE. 
g

Bias in a survey can be avoided by selecting random samples. TRUE. 
h

A sample for a survey on the study habits of all students in a secondary school is taken by selecting every 10th person on the alphabetical school roll. Would this produce a random sample? TRUE. 
i

In a random sample every member of the population has an equal chance of being selected. TRUE. 
j

A sur:vey which covers every member of a population is called an election. FALSE. 