QCEVault

Discrete random variables — Question 171

Original QCE Vault practice · 1 mark

Q171 · Practice questionTechnology-freeSimple familiar1 mark

QUESTION 171

A discrete random variable XX takes values 11, 22 and 44 with probabilities 0.20.2, 0.50.5 and 0.30.3 respectively. Determine E(X)E(X).
(A)
1.81.8
(B)
2.12.1
(C)
2.42.4
(D)
2.72.7
Question linkSyllabus coverage

Related questions

  1. Q5 · Original practice · 1 mark
    A discrete random variable XX has P(X=x)=k(x+1)P(X=x)=k(x+1) for x=0,1,2x=0,1,2. Determine kk.
    Discrete random variables
  2. Q15 · Original practice · 1 mark
    For a discrete random variable, P(X=0)=0.2P(X=0)=0.2, P(X=1)=0.5P(X=1)=0.5 and P(X=2)=0.3P(X=2)=0.3. Determine E(X)E(X).
    Discrete random variables
  3. Q25 · Original practice · 1 mark
    Let X∼Bin(3,0.4)X\sim\mathrm{Bin}(3,0.4). Determine P(X≥2∣X≥1)P(X\ge2\mid X\ge1), to three decimal places.
    Discrete random variables
  4. Q30 · Original practice · 3 marks
    Let X∼Bin(5,0.3)X\sim\mathrm{Bin}(5,0.3). Determine P(X=2)P(X=2) to four decimal places.
    Discrete random variables