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Discrete random variables — Question 172

Original QCE Vault practice · 1 mark

Q172 · Practice questionTechnology-activeSimple familiar1 mark

QUESTION 172

If

X\sim\operatorname{Bin}(6,0.3)

, then

P(X=2)

is closest to

(A)

0.185

(B)

0.324

(C)

0.420

(D)

0.744

ABCD

Question linkSyllabus coverage

WORKED SOLUTION

Answer B

1 mark

ANSWER

B

Worked solution

P(X=2)=\binom62(0.3)^2(0.7)^4\approx0.324

.

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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