Discrete random variables — Question 30
Original QCE Vault practice · 3 marks
Q30 · Practice questionTechnology-activeSimple familiar3 marks
QUESTION 30 (3 marks)
Let X∼Bin(5,0.3). Determine P(X=2) to four decimal places. WORKED SOLUTION
Practice marking scheme
3 marksWorked solution
P(X=2)=(25)(0.3)2(0.7)3=0.3087. Uses the binomial probability model with n=5, p=0.3. Forms (25)(0.3)2(0.7)3. Determines 0.3087. Practice question aligned to the current QCAA syllabus; review the worked solution and marking criteria.
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