Exam 6: Continuous Random Variables and the Normal Distribution

The normal probability distribution is applied to:

Use the following to answer questions : The daily sales at a convenience store produce a distribution that is approximately normal with a mean of 1220 and a standard deviation of 130. -The probability that the sales on a given day at this store are less than $1,305,rounded to four decimal places,is:

Use the following to answer questions : In a recent Gallup poll,52% of parents with children under 18 years of age gave themselves a grade of B for the job they are doing bringing up their kids.Assume that this percentage is true for the current population of all parents with children under 18 years of age.You take a random sample of 1044 such parents and ask them to give themselves a grade for the job they are doing bringing up their kids. -The probability that 520 to 555 will give themselves a grade of B is approximately: (Round the answer to 4 decimal places.)

The parameters of the normal distribution are:

A continuous random variable is a random variable that can:

Let x be a continuous random variable that follows a normal distribution with a mean of 207 and a standard deviation of 42. Find the value of x so that the area under the normal curve between and x is approximately 0.4996 and the value of x is greater than .Round your answer to two decimal places.

Use the following to answer questions : The daily sales at a convenience store produce a distribution that is approximately normal with a mean of 1220 and a standard deviation of 130. -The probability that the sales on a given day at this store are between $1,200 and $1,300,rounded to four decimal places,is:

We know that the length of time required for a student to complete a particular aptitude test has a normal distribution with a mean of 41.5 minutes and a variance of 3.1 minutes.What is the probability,rounded to four decimal places,that a given student will complete the test in more than 36 minutes but less than 44 minutes?

Use the following to answer questions : We know that football is the favorite sport to watch on television for 36% of adults in the United States.Suppose we take a random sample of 522 adults and obtain their opinions on their favorite sport to watch on television. -The probability that 193 or more will say that football is their favorite sport to watch on television is approximately: (Round the answer to 4 decimal places.)

For the standard normal distribution,the mean is:

For a continuous random variable x,the total probability of all (mutually exclusive)intervals within which x can assume a value is:

The total area under a normal distribution curve to the left of the mean is always:

Let x be a continuous random variable that follows a normal distribution with a mean of 200 and a standard deviation of 51. Find the value of x so that the area under the normal curve to the right of x is approximately 0.2946.Round your answer to two decimal places.

The ages of adults in a certain community follow a normal distribution with mean 38.5 and standard deviation 6.68.The random variable x represents the age of a randomly selected adult from this community.Given that ,what is a to the nearest year?