1. Sizes of adult male chinchillas are normally distributed with a mean length of 30.1 centimeters and a standard deviation of 2.75 centimeters. Find and interpret the percentile of a chinchilla which is 27.515 centimeters long.
2. Melville, an adult Ebony chinchilla, is 33.62 centimeters long. What percent of chinchillas have a length greater than Melville's?
3. A local chinchilla breeder enters several of her chinchillas in a national competition each year. Chinchillas which would fall in the smallest 25% of all chinchillas are entered in the "Bantam" category. What must a chinchilla's length be in order for it to be in the smallest 25% of all chinchillas?
4. In 2007, the band Radiohead allowed people to choose how much they wanted to pay to download their album In Rainbows. The distribution of payments was approximately norma with a mean of $8.05 and a standard deviation of $2.60.
5. Draw a normal curve and label the details provided by the 68-95-99.7 Rule for this scenario.
6. What range of prices would be considered "typical" - that is, what range of prices captures 68% of all prices paid to download In Rainbows?
7. What range of prices captures "almost all" (that is, 95% of) prices paid?
8. In 2010, the distribution of total tuition, room, and board costs for American public four-year universities was approximately normal with a mean of $15,040 and a standard deviation of $2100. What range do "almost all" (that is, 95% of) public universities fall in for the amount they charge in tuition, room, and board?
9. In 2010, total tuition, room, and board costs for an in-state student at NAU were approximately $15,502. Find and interpret the percentile of NAU's costs.