Answer:
The warranty the company should use is of 57,520 mile.
Step-by-step explanation:
Let X denote the tread life of a particular brand of tire.
It is provided that, [tex]X\sim N(60,000, 1600^{2})[/tex].
Also provided that the company wants 94% of the tires to outlast the warranty.
Let x denote the warranty .
That is, P (X > x) = 0.94.
⇒ P (X < x) = 0.06
⇒ P (Z < z) = 0.06
The corresponding value of z is -1.55.
*Use a z-table.
Compute the value of x as follows:
[tex]z=\frac{X-\mu}{\sigma}\\\\-1.55=\frac{x-60000}{1600}\\\\x=60000-(1.55\times 1600)\\\\x=57520[/tex]
Thus, the warranty the company should use is of 57,520 mile.
