Binominal distribution:
Given
Let 'T' be a random variable representing the number of ties that are too tight knotted.
Given approximately 10% of all businessmen who wear ties wear them so tightly that they actually reduce blood flow to the brain, hence, probability of success will be
pHence, the probability that at least one tie is too tight is
0.878423.
(b) more than two ties are too tight.
P
(
T
>
2
)
=
1
−
P
(
T
=
0
)
−
P
(
T
=
1
)
−
P
(
T
=
2
)
=
1
−
20
C
0
(
0.1
)
0
(
0.9
)
20
−
20. Related to this Question
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