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A certain tennis player makes a successful first serve 64​% of the time. Assume that each serve is independent of the others. If she serves 9 ​times, what's the probability she gets​

a) all 9 serves​ in?
b) exactly 6 serves​ in?
c) at least 7 serves​ in?
d) no more than 6 serves​ in?

User TonyWilk
by
6.4k points

1 Answer

4 votes

Answer:

0.0181,0.2693,0.1092,0.4163

Explanation:

Given that a certain tennis player makes a successful first serve 64​% of the time.

Since each serve is independent of the other

X the no of serves in is Binomial with n = no of times he serves =9

and p = constant probability = 0.64

X is Bin (9,0.64)

Probability that she get in

a) all 9 serves​ in?

=
P(X=9) = 0.64^9\\=0.0181

b) exactly 6 serves​ in?

P(x=6)

=
9C6 (0.64)^6 (1-0.64)^3\\=0.2693

c) at least 7 serves​ in

=
P(X\geq 7) = 0.1092

d) no more than 6 serves​ in

=
P(X<6)= 0.4163

User Erdikanik
by
6.7k points