Answer:
a. 0.2
b. 0.42
c. 0.7
d. the solution is in the explanation
e. x and y are not independent
Step-by-step explanation:
a. from the joint probability mass function table,
p(x=1) and p(Y= 1)
= p(1,1) = 0.2
b. prob(0,0)+prob(0,1)+prob(1,0)+prob(1,1)
= 0.10 + 0.04 + 0.08 + 0.20
= 0.42
P(X ≤ 1 and Y ≤ 1) = 0.42
c. prob {X ≠ 0 and Y ≠ 0}
= prob(1,1) + prob(1,2) + prob(2,1) + prob(2,2)
= 0.20 + 0.06 + 0.14 + 0.30
= 0.7
d. we have to calculate the marginal pmf of x and y here.
<u>we have the x values as 0,1,</u>2
prob(x=0) = 0.1 + 0.04 + 0.02
= 0.16
prob(x=1) = 0.08 + 0.2 + 0.06
= 0.34
prob(x=2) = 0.06+0.14+0.3
= 0.50
<u>we have y values as 0,1,2</u>
prob(y=0) = .1+.08+.06
= 0.24
prob(y=1) = .04+.2+.14
= 0.38
prob(y = 2) = 0.02+0.06+0.3
= 0.38
P(X ≤ 1) = prob(x=0)+prob(x=1)
= 0.34+0.16
= 0.50
e. from the joint table we have this,
prob(1,1) = 0.2
prob(x=1) = 0.34
prob(y=1) = 0.38
then prob(x=1)*prob(y=1)
= 0.34*0.38
= 0.1292
therefore prob(1,1) is not equal to prob(x=1)*prob(y=1)
0.2≠0.1292
x and y are not independent
