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A survey was conducted to measure the height of U.S. men.  In the survey, respondents were grouped by age.  In the 20-29 age group, the heights were normally distributed, with a mean of 69.6 inches and a standard deviation of 3.0 inches.  A study participant is randomly selected.

1. Find the probability to three significant figures that his height is less than 66 inches.  {#1}
   
   
2. Find the probability to three significant figures that his height is between 66 and 72 inches.  {#2}
   
   
3. Find the probability to three significant figures that his height is more than 72 inches. {#3}

The lengths of Atlantic croaker fish are normally distributed, with a mean of 10 inches and a standard deviation of 2 inches.  An Atlantic croaker fish is randomly selected.

1. Find the probability to three significant figures that the length of the fish is less than 7 inches.  {#1}
   
2. Find the probability to three significant figures that the length of the fish is between 7 and 15 inches.  {#2}
   
   
3. Find the probability to three significant figure that the length of the fish is more than 15 inches.  {#3}

In a recent year, the ACT scores for high school students with a 3.50 to 4.00 grade point average were normally distributed, with a mean of 24.2 and a standard deviation of 4.3.  A student with a 3.50 to 4.00 grade point average who took the ACT during this time is randomly selected.

1. Find the probability to three significant figures that the student's ACT score is less than 17.  {#1}
   
   
2. Find the probability to three significant figures that the student's ACT score is between 20 and 29.  {#2}
   
   
3. Find the probability to three significant figures that the student's ACT score is more than 32.  {#3}

The weights of adult male beagles are normally distributed, with a mean of 25 pounds and a standard deviation of three pounds.  A beagle is randomly selected.

1. Find the probability to three significant figures that the beagle's weight is less than 23 pounds.  {#1}
   
2. Find the probability to three significant figures that the beagle's weight is between 23 and 25 pounds.  {#2}
   
   
3. Find the probability to three significant figures that the beagle's weight is more than 27 pounds.  {#3}

A survey was conducted to measure the number of hours per week adults in the United states spend on home computers.  In the survey, the number of hours were normally distributed, with a mean of 7 hours and a standard deviation of 1 hour.  A survey participant is randomly selected.

1. Find the probability to three significant figures that the hours spent on the home computer by the participant are less than 5 hours per week.  {#1}
   
   
2. Find the probability to three significant figures that the hours spent on the home computer by the participant is between 5.5 and 9.5 hours per week.  {#2}
   
   
3. Find the probability to three significant figures that the hours spent on the home computer by the participant are more than 10 hours per week.  {#3}

The monthly utility bills in a city are normally distributed with a mean of $100 and a standard deviation of $12.  A utility bill is randomly selected.

1. Find the probability to three significant figures that the utility bill is less than $70.  {#1}
   
2. Find the probability to three significant figures that the utility bill is between $90 and $120.  {#2}
   
   
3. Find the probability to three significant figures that the utility bill is more than $140.  {#3}

The time per week a student uses a lab computer is normally distributed, with a mean of 6.2 hours and a standard deviation of 0.9 hour.  A student is randomly selected.

1. Find the probability to three significant figures that the student uses a lab computer less than 4 hours per week.  {#1}
   
2. Find the probability to three significant figures that the student uses a lab computer between 5 and 7 hours per week.  {#2}
   
   
3. Find the probability to three significant figures that the student uses a lab computer more than 8 hours a week.  {#3}

The time per workout an athlete uses a stairclimber is normally distributed, with a mean of 20 minutes and a standard deviation of 5 minutes.  An athlete is randomly selected.

1. Find the probability to three significant figures that the athlete uses a stairclimber for less than 17 minutes.  {#1}
   
2. Find the probability to three significant figures that the athlete uses a stairclimber between 20 and 28 minutes.  {#2}
   
   
3. Find the probability to three significant figures that the athlete uses a stairclimber more than 30 minutes.  {#3}

The normal distribution of SAT critical reading scores for a certain year has a mean of 503 and a standard deviation of 113.

1. What percent (to three significant figures) of the SAT verbal scores are less than 600?
   {#1}%
   
   
2. If 1000 SAT verbal scores are randomly selected, about how many would you expect to be greater than 550? (round your answer to the test result)
   {#2}

The normal distribution of SAT math scores for a certain year has a mean of 518 and a standard deviation of 115.

1. What percent (to three significant figures) of the SAT math scores are less than 500?
   {#1}%
   
   
2. If 1500 SAT math scores are randomly selected, about how many would you expect to be greater than 600? (round your answer to the test result)
   {#2}

The normal distribution of U.S. woman's total cholesterol levels in the age group of 20-34 has a mean of 186 milligrams per deciliter and a standard deviation of of 35.8 milligrams per deciliter.

1. What percent of the women (to three significant figures)  have a total cholesterol level less than 200 milligrams per deciliter of blood?
   {#1}%
   
   
2. If 250 U.S. women in the 20-34 age group are randomly selected, about how many would you expect to have a total cholesteral level greater than 240 milligrams per deciliter of blood?  (round your answer to the nearest woman)
   {#2} women

The normal distribution of U.S. woman's total cholesterol levels in the age group of 55-64 has a mean of 219 milligrams per deciliter and a standard deviation of of 41.6 milligrams per deciliter.

1. What percent of the women (to three significant figures)  have a total cholesterol level less than 239 milligrams per deciliter of blood?
   {#1}%
   
   
2. If 200 U.S. women in the 55-64 age group are randomly selected, about how many would you expect to have a total cholesteral level greater than 200 milligrams per deciliter of blood?  (round your answer to the nearest woman)
   {#2} women

The normal distribution for Atlantic croaker fish lengths has a mean of 10 inches and a standard deviation of 2 inches.

1. What percent (to three significant figures) of fish are longer than 11 inches?
   {#1}%
   
   
2. If 200 Atlantic croakers are randomly selected, about how many would you expect to be shorter than 8 inches?  (round to the nearest fish)
   {#2} fish

The normal distribution of the weight of adult male beagles has a mean of 25 pounds and a standard deviation of 3 pounds.

1. What percent (to three significant figures) of the beagles have a weight that is greater than 30 pounds?
   {#1}%
   
   
2. If 50 beagles are randomly selected, about how many would you expect to weight less than 22 pounds? (round your answer to the nearest beagle)
   {#2} beagles

The normal distribution of home computer use in U.S adults has a mean of 7 hours and a standard deviation of 1 hour.

1. What percent (to three significant figures) of adults spend more than 4 hours per week on a home computer?
   {#1}%
   
   
2. If 35 adults in the United States are randomly selected, about how many would you expect to say they spend less than 5 hours per week on a home computer?  (round your answer to the nearest adult)
   {#2} adult(s)

The normal distribution of monthly utility bills in a city has a mean of $100 and a standard deviation of $12.

1. What percent (to three significant figures) of the utulity bills are more than $125?
   {#1}%
   
   
2. If 300 utility bills are randomly selected, about how many would you expect to be less than $90?  (round your answer to the nearest bill)
   {#2} bill(s)

The life span of a battery is normally distributed, with a mean of 2000 hours and a standard deviation of 30 hours.  

1. What percent (to three significant figures) of batteries have a life span that is more than 2065 hours?
   {#1}%
   
   
2. Would it be unusual for a battery to have a life span that is more than 2065 hours?
   {#2}

Assume the mean annual consumption of peanuts is normally distributed, with a mean of 5.9 pounds per person and a standard deviation of 1.8 pounds per person.  

1. What percent (to three significant figures) of people annually consume less than 3.1 pounds of peanuts per person?
   {#1}%
   
   
2. Would it be unusual for a person to consume less than 3.1 pounds of peanuts in a year?
   {#2}