A manufacturer claims that the life span of its tires is 47,000 miles. You work for a consumer protection agency and you are testing these tires. Assume the life spans of the tires are normally distributed. You select 100 tires at random and test them. The mean life span is

46,833 miles.

Assume sigma=700

.

Complete parts (a) through (c).

(a) Assuming the manufacturer's claim is correct, what is the probability that the mean of the sample is

46,833 miles or less?

(Round to four decimal places as needed.)

(b) Using your answer from part (a), what do you think of the manufacturer's claim?

The claim is( inaccurate or accurate) because the sample mean (would or would not) be considered unusual since it

(does not lie or lies)

within the range of a usual event, namely within

1 standard deviation

2 standard deviations

3 standard deviations

of the mean of the sample means.

(c) Assuming the manufacturer's claim is true, would it be unusual to have an individual tire with a life span of

46.833 miles? Why or why not?

Yes or No because 46,833 (does not lie or lies within the range of a usual event, namely within

1 standard deviation

2 standard deviations

3 standard deviations

of the mean for an individual tire.