In: Statistics and Probability
x | 0 | 1 | 2 | 3 | 4 |
P(X) | .45 | .3 | .2 | .04 | .01 |
(c) Find the probability that a person has 1 sibling given that they have less than 3 siblings. Hint: Use the conditional formula: P(A|B)=P(A and B)/P(B). In this case A: event of having 1 sibling and B: event of having less than 3 siblings.
(d) Find the probability that a person has at least 1 sibling OR less than 2 siblings. Hint: Use the General Addition Rule: P(A or B)=P(A)+P(B)-P(A and B). In this case A: event of having at least 1 sibling and B: event of having less than 2 siblings.
x | 0 | 1 | 2 | 3 | 4 |
p(x) | 0.45 | 0.3 | 0.2 | 0.04 | 0.01 |
c)
Here,
Now
Therefore, the probability that a person has 1 sibling given that they have less than 3 siblings is 0.4737
d)
Here
And
Now
Therefore, the probability that a person has at least 1 sibling OR less than 2 siblings = 1