2. Listed below are recorded speeds (in km/hr) of randomly selected cars travelling on a section of SCTEX. That part of the express way has posted an average speed limit of 100 km/hr. Use a 0.01 significance level to test the claim that the vehicles do not exceed or is travelling at most the speed limit. 98 110 87 105 | 120 | 75 | 80 65 102 95 90 77 105 100 • Claim: Họ: Vs. H.: • Test statistic to use: Tail of the distribution: • Reject Ho if Computation: • Decision: Conclusion:

Suppose that on a certain section of I-95, with a posted speed limit of 65 miles per hour, the speeds of all vehicles have a bell-shaped distribution with a mean of 72 mph and a standard deviation of 3 mph. Find the percentage of vehicles with the following speeds on this section of I-95: greater than 75 mph.

Please answer the following: You can use the graphing calculator-just explain how to input into calculator. A tire manufacturer beleives that the tread life of its snow tires can be described by a normal model with a mean of 32,000 miles and standard deviation of 2,500 miles. a) If you buy a set of these tires, would it be reasonable for you to hope that they last 40,000 miles? Explain. b) What proportion of these tires can be expected to last less than 30,000 miles? c) What proportion of these tires can be expected to last between 30,000 and 35,000 miles? d) Estimate the IQR of the tread lives.   e) In planning a marketing strategy, a local tire dealer wants to offer a refund to any customer whose tires fail to last a certain number of miles. However, the dealer does not want to take too big a risk. If the dealer is willing to give refunds to no more than 1 of every 25 customers, for what mileage can he be guaranteed these tires to last?

Suppose that a customer is purchasing a car. He conducts an experiment in which he puts 10 gallons of gas in the car and drives it until it runs out of gas. He conducts this experiment 15 Sample mean for Car 2 x= 245 mi / 10 gal (Type an integer or decimal rounded to one decimal place as needed.) times on each car and records the number of miles driven. Full data set Car 1 Median for Car 1 M= mi / 10 gal (Type an integer or decimal rounded to one decimal place as needed.) 245 242 215 244 220 265 291 160 284 251 169 319 257 306 267 Car 2 Median for Car 2 230 242 M=O mi / 10 gal 206 214 236 256 245 255 241 264 (Type an integer or decimal rounded to one decimal place as needed.) 276 252 250 251 257