Statistical inference — Question 3

QCAA 2020, Paper 1 · 1 mark

Q3 · 2020 · Technology-freeSimple familiar1 mark

QUESTION 3

According to a recent census, the mean hours worked per week by all Australian workers is

35.6

hours.

A mean of

36.1

hours worked per week is calculated from a random selection of

500

Australian workers.

Based on this data, which of the following is correct?

(A)

\bar{x}=35.6,\;\mu=36.1

(B)

\bar{x}=35.6,\;\bar{X}=36.1

(C)

\bar{x}=36.1,\;\mu=35.6

(D)

\bar{x}=36.1,\;\bar{X}=35.6

ABCD

Question linkOriginal paper

WORKED SOLUTION

Answer C

1 mark

ANSWER

Worked solution

The census value describes the population mean, so

\mu=35.6

. The mean from the sample is the observed sample mean,

\bar{x}=36.1

Selects option C.

[1 mark]

Worked explanation by QCE Vault; correct option verified against the QCAA answer key.

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