In each
trial, p = probability of hitting the target = 3
4  and q  =  probability of not hitting the
target = 1
4 Then  P(X = x) = 
1
3
3
C
C
C
4
4
4
n x
x
x
n
n x
x
n
n
x
x
x
n
q
p
−
−
⎛
⎞
⎛
⎞
=
=
⎜
⎟
⎜
⎟
⎝
⎠
⎝
⎠ Now, given that,
P(hitting the target at least once) > 0 99
i