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Discrete random variables — Question 15

Original QCE Vault practice · 1 mark

Q15 · Practice questionTechnology-freeSimple familiar1 mark

QUESTION 15

For a discrete random variable,

P(X=0)=0.2

,

P(X=1)=0.5

and

P(X=2)=0.3

. Determine

E(X)

.

(A)

0.8

(B)

1.1

(C)

1.3

(D)

1.5

ABCD

Question linkSyllabus coverage

WORKED SOLUTION

Answer B

1 mark

ANSWER

B

Worked solution

E(X)=0(0.2)+1(0.5)+2(0.3)=1.1

.

Selects the correct option.

[1 mark]

Practice question aligned to the current QCAA syllabus; review the worked solution and marking criteria.

View the QCAA syllabus

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