Question

die is thrown 4 times. If getting an odd number is a success, then the probability of getting exactly two successes is .... *​

Answer 1

Step-by-step explanation:

SOLUTION

Let X denote the number of odd numbers.

P(getting and odd number) = p =

36=12

∴ q = 1 – p =

1-12=12

Given, n = 4

∴ X ∼ B

(4,12)

The p.m.f. of X is given by

P(X = x) =

4Cx(12)x(12)4-x

=

4Cx(12)4,x = 0, 1,...,4

P(at most 2 successes)

= P(X ≤ 2)

= P(X = 0 or X = 1 or X = 2)

= P(X = 0 + P(X = 1) + P(X = 2)

=