1. On average, indoor cats live to 13 years old with a standard deviation of 2.2 years. Suppose that the distribution is normal. Let X = the age at death of a randomly selected indoor cat. Round answers to 4 decimal places where possible. A.  The middle 20% of indoor cats' age of death lies between what two numbers?      Low:  years High:  years

1. On average, indoor cats live to 13 years old with a standard deviation of 2.2 years. Suppose that the distribution is normal. Let X = the age at death of a randomly selected indoor cat. Round answers to 4 decimal places where possible.

A.  The middle 20% of indoor cats' age of death lies between what two numbers?
     Low:  years High:  years

2. The average American man consumes 9.5 grams of sodium each day. Suppose that the sodium consumption of American men is normally distributed with a standard deviation of 1 grams. Suppose an American man is randomly chosen. Let X = the amount of sodium consumed. Round all numeric answers to 4 decimal places where possible.

B. The middle 20% of American men consume between what two weights of sodium?
Low:  High: 

3. Terri Vogel, an amateur motorcycle racer, averages 129.55 seconds per 2.5-mile lap (in a 7 lap race) with a standard deviation of 2.26 seconds. The distribution of her race times is normally distributed. We are interested in one of her randomly selected laps. (Source: logbook of Terri Vogel) Let X be the number of seconds for a randomly selected lap. Round all answers to 4 decimal places where possible.


C. The middle 40% of her laps are from_____seconds to____seconds.