1. A random variable X is best described by a continuous uniform distribution from 20 to 45 inclusive. The mean of this distribution is:

Select one:

1. 30.5
2. 31.5
3. 32.5
4. 33.5

A random variable X is best described by a continuous uniform distribution from 20 to 45 inclusive. The standard deviation of this distribution is approximately:

Select one:

1. 52.1
2. 32.5
3. 6.85
4. 7.22

3. A random variableXis best described by a continuous uniform distribution from 20 to 45 inclusive. What isP(30 ?X? 40)?

a. 20 b. 40 c. 60 d 80

4. What are the mean and standard deviation for the standard normal distribution?

a. ?= 0,?= 0

b. ?= 1,?= 1

c. ?= 1,?= 0

d. ?= 0,?= 1

5. Any two normal curves are the same except for their:

a. standard deviations

b. means

c. standard deviations and means

d. standard deviations, means, skewness, and kurtosis

6. Which is the correct Excel formula for the 80th percentile of a distribution that is N(475, 33)?

a. NORM.DIST(80,475,33,1

b. NORM.INV(0.80,475,33)

c. NORM.S.INV((80-475)/33)

7.In a continuous distribution:

a. P(XP(X? 5)

b. P(XP(X? 5).

c. P(XP(X? 5).

8.The figure shows a normal N(400, 23) distribution. Find the x value for the shaded area.

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