A purchasing agent for a trucking company is shopping for replacement tires for their trucks from two suppliers. The suppliers' prices are the same. However, Supplier A's tires have an average life of 60,000 miles with a standard deviation of 10,000 miles. Supplier B's tires have an average life of 60,000 miles with a standard deviation of 2,000 miles. Which of the following statements is true? The two distributions of tire life are the same. On average, Supplier A's tires have a longer life than Supplier B's tires. The life of Supplier B's tire is more predictable than the life of Supplier A's tires. The dispersion of Supplier A's tire life is less than the dispersion of Supplier B's tire life. 2.What is the relationship among the mean, median, and mode in a symmetric distribution? They are all equal. The mean is always the smallest value. The mean is always the largest value. The mode is the largest value. 3.According to Chebyshev's theorem, at least what percent of the observations lie within plus and minus 1.75 standard deviations of the mean? 56% 95% 67% 100% 4.A sample of wires coming off the production line was tested for tensile strength. The statistical results (in PSI) were the following: math.png According to the Empirical rule, the middle 95% of the wires tested had a tensile strength between approximately what two values? 450 and 550 460 and 540 420 and 580 380 and 620 5.The same mean: Is always equal to the population mean. Is always smaller than the population mean. Is found by adding the data values and dividing them by (n-1). Is found by adding all data values and dividing them by n. 6.What is a disadvantage of the range as a measure of dispersion? It is based on only two observations. It can be distorted by a large mean. It is not in the same units as the original data. It has no disadvantage. 7.A sample of single persons receiving Social Security payments revealed these monthly benefits: $826, $699, $1,087, $880, $839, and $965. How many observations are below the median? 1 2 3 3.5 8.The monthly amounts spent for food by families of four receiving food stamps approximates a symmetrical, normal distribution. The sample mean is $150 and the standard deviation is $20. Using the Empirical rule, about 95% of the monthly food expenditures are between what two amounts? $100 and $200 $85 and $105 $205 and $220 $110 and $190 9.A sample of small bottles and their contents has the following weights (in grams): 4, 2, 5, 4, 5, 2, and 6. What is the sample variance of bottle weight? 6.92 4.80 1.96 2.33 10.A sample of assistant professors on the business faculty at state-supported institutions in Ohio revealed the mean income to be $72,000 for nine months, with a standard deviation of $3,000. Using Chebyshev's theorem, what proportion of the faculty earns more than $66,000, but less than $78,000? At least 50% At least 25% At least 75% At least 100% 11.The following are the weekly amounts of welfare payments made by the federal government to a sample of six families: $139, $136, $130, $136, $147, and $136. What is the range? $0 $14 $52 $17 12.For any data set, which measures of central location have only one value? Mode and median Mode and mean Mode and standard deviation Mean and median