Discrete random variables — Question 173
Original QCE Vault practice · 1 mark
Q173 · Practice questionTechnology-freeSimple familiar1 mark
QUESTION 173
The probability distribution of X is shown. Determine E(X). 
WORKED SOLUTION
Answer C
1 markWorked solution
E(X)=0(0.15)+1(0.25)+2(0.35)+3(0.25)=1.70. 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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