Calcul de probabilités - Maths en classes préparatoires

ed
n◦
88%
20% 15%
•
•
•

9
10
F¯ F
F
¯
F
•
•
1
11 .
T
p(T∩F) = 9
10 p(T∩¯
F) = 1
110
T p(F/T ).
0.8 0.5
0.7
n1n(n∈N∗)k
n k (n−k)
n U1, U2, ..., Un(n∈N∗)Ukn
k(n−k)

Ωp
A B
p(A) = 0.8; p(B) = 0.3; p(A∪B) = 0.86
p(A/B).
A B
C p(B∩C/A) = 0.2
p(C∪¯ A∪¯ B).
5%
96%
98%
A”M1”B”
M2”
M11
3
M21
4.
M1
p(A) = 3
8, p(B) = 5 8, p(A∪B) = 3 4
p(A/B)p(B/A).
A B
U1U2

U1
95%
5%
3
5.
(n+ 5) (n+ 3)
pn1
2
(n+5)(n+10)
(n+7)2.
pn>1
2
A B Ω (B6= Ω)
p(A/¯
B) = p(A)−p(A/B).p(B)
1−p(B)
•30%
•40%
b(b6= 1)
b p
b p
0.1
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