State clearly what the random variable represents.
X represents the number of hits that Sally has in a softball match. X= 0, 1, 2, 3, 4, 5
Find k.
k = 0.23
Find the probability that Sally has at least two hits in the softball game.
0.79
Find the probability that Sally has between 1 and 3 hits in the game, inclusive.
P(1 <= X <= 3) = 0.83
What is the mode?
3 hits is the mode
What is the median?
the median is 3 hits
Is the following a valid probability mass function? Why?
Yes
Is the following a valid probability mass function? Why?
Yes
a) i
Naomi
a) ii
Rosslyn
b) (remember what that means... you are finding the exp...)
Rosslyn because she is expected to earn 5.94 points per shot as opposed to 5.7 points for Naomi.
Find a and b.
a = 0.15 and b = 0.35
Find E(X).
E(X) = 2.1
a)
X = the number of threes spun, only one - so it either is spun (p = 1/5) or not (1-p = 4/5)
b)
mu = 4 ; sigma = 1.79
a)
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