1) Tire Life - The life of a tire is normally distributed with a mean of 76,000 miles and a standard deviation of 10,000 miles.
a) Determine the probability that a tire will last for less than 67,000 miles.
b) Determine the probability that a tire will last for more than 67,000 miles.
c) Determine the probability that a tire will last for less than 80,000 miles.
d) Determine the probability that a tire will last between 67000 and 80000 miles?
e) The company offers a warranty. The warranty costs $8 per tire returned. If the company sets the warranty miles at 67000, how much on average per tire will the warranty cost?
2) Church Fund Raiser - The amount of money earned at the church charity auction for the last 20 years is in the following table. Assume a normal distribution. (Use Excel)
What is the mean?
Year Amount
1 349
2 280
3 390
4 470
5 380
6 430
7 290
8 477
9 298
10 449
11 370
12 375
13 405
14 490
15 402
16 410
17 330
18 510
19 325
20 370
What is the standard deviation?
What is the probability that the church will earn less than $425 next year?
What is the probability that the church will earn more than $425 next year?
What is the probability that the amount will be between $400 and $475?