SOLUTION: A fair coin is tossed 10 times. Let X denote the number of heads obtained. Find the following. (a) P(X = 7) (b) P(X ≤ 7) (c) P(X > 0) (d) E(X) and Var(X)

Algebra ->  Probability-and-statistics -> SOLUTION: A fair coin is tossed 10 times. Let X denote the number of heads obtained. Find the following. (a) P(X = 7) (b) P(X ≤ 7) (c) P(X > 0) (d) E(X) and Var(X)      Log On


   

Question 1177761: A fair coin is tossed 10 times. Let X denote the number of heads obtained. Find the following.
(a) P(X = 7)
(b) P(X ≤ 7)
(c) P(X > 0)
(d) E(X) and Var(X)
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!

Hi
Binomial Distribution:  p(H) = .5  and q(T) = .5
n = 10
Using TI or similarly an inexpensive calculator like a Casio fx-115 ES plus
(a) P(X = 7) = .1172
(b) P(X ≤ 7) = .9453
(c) P(X > 0) = 1 - P(x=0) = 1- .00098 = .99902
(d) E(X) and Var(X)
E(X) = .5*10 = 5
Var(X) = npq = .5*10*.5 = 2.5
Wish You the Best in your Studies.