Mathematical Methods — Question 4

QCAA 2024, Paper 2 · 1 mark

Q4 · 2024 · Technology-activeSimple familiar1 mark

QUESTION 4

Consider the Bernoulli distribution where the outcomes for rolling a six-sided die are a four and not rolling a four. Determine the variance of the resulting Bernoulli distribution in this scenario.

(A)

0.02\dot7

(B)

0.13\dot8

(C)

0.1\dot6

(D)

0.8\dot3

ABCD

Question linkOriginal paper

WORKED SOLUTION

Answer B

1 mark

ANSWER

B —

0.13\dot8

Worked solution

Here

p=1/6

. A Bernoulli variance is

p(1-p)=\frac16\frac56=\frac5{36}=0.13888\ldots

, so option B.

Selects option B.

[1 mark]

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

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Mathematical Methods — Question 4

QUESTION 4

Answer B

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