Respuesta :
Answer:
The probability that all will last at least 30,000 miles is 0.3164.
Step-by-step explanation:
Consider the provided information.
For a particular tire brand, the probability of wearing out before 30,000 miles is 0.25. Someone who buys a set of four of these tires,
That means the probability of not wearing out is 1-0.25 = 0.75
Now use the binomial distribution formula.
[tex]^nC_r (p^{n-r})(q^r)[/tex]
Substitute p = 0.25, q=0.75, r=4 and n=4
[tex]^4C_4 (0.25)^{4-4}(0.75)^4[/tex]
[tex]1 \times 0.75^4[/tex]
[tex]0.3164[/tex]
The probability that all will last at least 30,000 miles is 0.3164.
