Help with probability please?
1) A small train at an amusement park is carrying passengers. Half of the passengers are 6 years old, 1/10 are 7 years old, 1/5 are 8 years old and 1/5 are 9 years old. What is the expected age for one of the passengers on the train?
A) 6 years
B)7.1 years
C)8 years
D) 8.5 years

2)Which probability distribution table corresponds with this frequency table?

X 1 2 3 4 5
F 3 7 2 3 5

A) X 1 2 3 4 5
P 0.3 0.7 0.2 0.3 0.5

B) X 1 2 3 4 5
P 0.2 0.2 0.2 0.2 0.2

C X 1 2 3 4 5
P 0.15 0.35 0.1 0.15 0.25

D) X 1 2 3 4 5
P 1.5 3.5 1 1.5 2.5

Question

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Respuesta :

Аноним Аноним · Answer 1 · 2019-03-08T08:13:38+01:00

Answer:

1.)

Number of passengers who are 6 years old [tex]=\frac{1}{2}[/tex]

Number of passengers who are 7 years old [tex]=\frac{1}{10}[/tex]

Number of passengers who are 8 years old [tex]=\frac{1}{5}[/tex]

Number of passengers who are 9 years old [tex]=\frac{1}{5}[/tex]

E(X=6+X=7+X=8+X=9)

=6 × P(6) +7 ×P(7)+8×P(8)+9×P(9)

[tex]=6\times \frac{1}{2}+7\times \frac{1}{10}+8\times \frac{1}{5}+9\times \frac{1}{10}\\\\ =3+0.7+1.6+0.9\\\\ =3+2.3+0.9\\\\=6.2[/tex]

Option A :6 (approx) ,appears true.

2.)

Sum of total frequency =3+7+2+3+5=20

[tex]P(1)=\frac{3}{20}=0.15, P(2)=\frac{7}{20}=0.35,P(3)=\frac{2}{20}=0.10, P(4)=\frac{3}{20}=0.15,P(6)=\frac{5}{20}=0.25[/tex]

Option C: X 1 2 3 4 5

P 0.15 0.35 0.10 0.15 0.25

is true.