1. In its standardized form, the normal distribution
a) has a mean of 0 and a standard deviation of 1.
b) has a mean of 1 and a variance of 0.
c) has an area equal to 0.5.
d) cannot be used to approximate discrete probability distributions.

2. For some positive value of Z, the probability that a standard normal variable is between 0 and Z is 0.3770. Find value of Z?

3. For some value of Z, the probability that a standard normal variable is below Z is 0.2090. Find value of Z?

4. For some positive value of X, the probability that a standard normal variable is between 0 and +2X is 0.1255. Find value of X?

For 2,3,4 I need detail calculation and explanation.

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1. In its standardized form, the normal distribution
a) has a mean of 0 and a standard deviation of 1. < True
b) has a mean of 1 and a variance of 0.
c) has an area equal to 0.5.
d) cannot be used to approximate discrete probability distributions.

2. For some positive value of Z, the probability that a standard normal ...

In itsstandardizedform,thenormaldistribution
a. has an area equal to 0.5.
b. has a mean of 0 and a standard deviation of 1.
c. has an area equal to 100.
d. has a mean of 1 and a variance of 0.

1. For a standardizednormaldistribution calculate the following probabilities
a. P(0.00 < z < or equal to 2.33)
b. P( -1.00 < z < or equal to 1.00)
c. P( 1.78 < z < 2.34).
2. A random variable is normally distributed with mean of 25 and standard deviation of 5. If an observation is randomly selected
a. what val

Thedistribution of scores on a standardized aptitude test is approximately normal with a mean of 500 and a standard deviation of 105 . What is the minimum score needed to be in the top 25% on this test? Carry your intermediate computations to at least four decimal places, and round your answer to the nearest integer.

A large population of metal rods have an average diameter of .943 inches with a standard deviation of .001 inches. The engineering specification for the rods requires that they be between .941 and .944 inches. Using thestandardizednormal table, determine the percentage of the population that should meet the requirement. Draw a

Let x be a random variable that represents the length of time it takes a student to write a term paper for Dr. Adam's Sociology class. After interviewing many students, it was found that x has an approximately normaldistribution with mean μ = 6.8 hours and standard deviation σ = 2.1 hours.
Convert each of the foll

A distribution with a mean of 38 and a stand deviation of 20 is being transformed into a standardizeddistribution with mean of 50 and standard deviation of 10 find the new standardized score for each of the following scores from the original population.
X= 48
X= 30
X= 40
X= 18

When we move from the basic normaldistribution to the sampling distribution of the mean we substitute the standard error of the mean for the standard deviation when we make the conversion to thestandardizednormaldistribution. Why do we use the standard error of the mean in this case? And how does using the standard error aff

Thedistribution of scores on a standardized aptitude test is approximately normal with a mean of 520 and a standard deviation of 100. What is the minimum score needed to be in the top 20% on this test? Carry your intermediate computations to at least four decimal places, and round your answer to the nearest integer.