Discrete random variables — Question 25
Original QCE Vault practice · 1 mark
Q25 · Practice questionTechnology-activeComplex unfamiliar1 mark
QUESTION 25
Let X∼Bin(3,0.4). Determine P(X≥2∣X≥1), to three decimal places. WORKED SOLUTION
Answer C
1 markWorked solution
P(X≥2)=0.352 and P(X≥1)=1−0.63=0.784. Hence the conditional probability is 0.352/0.784≈0.449. Selects the correct option.
[1 mark]Practice question aligned to the current QCAA syllabus; review the worked solution and marking criteria.
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