Respuesta :

Answer:

0.96

Step-by-step explanation:

Given that the a die is rolled 8 number of times.

[tex]n[/tex] = 8

Probability of getting a 6 on roll of a die,  [tex]p=\frac{1}{6}[/tex]

Probability of not getting a 6 on roll of a die,  [tex]q=1-p=1-\frac{1}{6}=\frac{5}{6}[/tex]

Probability of getting 6 three or fewer times:

[tex]P(r \le 3)=P(r=0)+P(r=1)+P(r=2)+P(r=3)[/tex]

Formula:

[tex]P(r=k)=_nC_k.p^k.q^{n-k}[/tex]

Putting the values using this formula:

[tex]P(r \le 3)=_8C_0.\frac{1}{6}^0.\frac{5}{6}^{8-0}+_8C_1.\frac{1}{6}^1.\frac{5}{6}^{8-1}+_8C_2.\frac{1}{6}^2.\frac{5}{6}^{8-2}+_8C_3.\frac{1}{6}^3.\frac{5}{6}^{8-3}\\\Rightarrow P(r \le 3)=1.\frac{5}{6}^{8}+8.\frac{1}{6}.\frac{5}{6}^{7}+28.\frac{1}{36}^2.\frac{5}{6}^{6}+56.\frac{1}{216}.\frac{5}{6}^{5}\\\Rightarrow P(r \le 3)=0.23+0.37+0.26+0.1=\bold{0.96}[/tex]