1. a researcher notes that the weight of a male golden retriever is approximately normally distributed with a mean of 70 lbs and a standard deviation of 7.5 lbs. what percentage of these dogs weigh less than 65 lbs?a. 75%b. 25%c. 5%d. 33.3%e. 66.7%
2. a companys manufacturing process uses 500 gallons of water at a time. A “scrubbing” machine then removes most of a chemical pollutant before pumping the water into a nearby lake. to meet federal regulations the treated water must not contain more than 80 parts per million (ppm) of the chemical. because a fine is charged if regulations are not met, the company sets the machine to attain an average of 75 ppm in the treated water. the machine’s output can be described by a normal model with standard deviation 4.2 ppm. what percent of the batches of water discharged exceed the 80 ppm standard?a. 3.89%
b. 1.17%
c. 88.3%
d. 11.7%
e. 8.83%
3. based on data collected from its production processes, crosstiles inc. determines that the breaking strength of its most popular porcelain tile is normally distributed with a mean of 400 pounds per square inch and a standard deviation of 12.5 pounds per square inch. Based on the 68-95-99.7 rule, about what percent of its popular porcelain tile will have breaking strengths between 375 and 425 pounds per square inch?a. 32%b. 84%c. 95%d. 68%e. 47.5%
4. the ASQ (american society for quality) regularly conducts a salary survey of its membership, primarily quality management professionals. Based on the most recently published mean and standard deviation, a quality control specialist calculated the z-score associated with his own salary and found it was -2.50. This tells him that his salary isa. 2.5 standard deviation above the average salary
b. 2 and a half times less than the average salary
c. 2 and a half times more than the average salary
d. much higher than the average salary
e. 2.
5 standard deviations below the average salary5. adult female dalmatians weigh an average of 50 pounds with a standard deviation of 3.3 pounds. Adult female boxers weigh an average of 57.6 pounds with a standard deviation of 1.7 pounds. one statistics teacher owns an underweight dalmatian and an underweight boxer. the dalmatian weighs 45 pounds, the boxer weighs 52 pounds. which dog is more underweight?a. the dalmatian because it is 5 pounds underweight
b. the boxer because it is 9.6% underweight
c. the boxer because it is 5.5 pounds underweight
d. the dalmatian because it is 9.6% underweight
e. the boxer because it is 3.24 standard deviations underweightso far i’ve started one and I got 0.66 but i know that’s not right