Assume that the variable under consideration has a density curve. The area under the density curve that lies to the right of 10 is 0.427.

a. What percentage of all possible observations of the variable exceed 10?

b. What percentage of all possible observations of the variable are at most 10?

a. ( ? ) %

(Type an integer or adecimal.)

4 Assume that the variable under consideration has a density curve. The area under the density curve that lies between 17 and 21 is 0.594. What percentage of all possible observations of the variable are either less than 17 or greater than 21?

% (Type an integer or a decimal. Do notround.

5 A curve has area 0.641 to the left of 65 and area 0.459 to the right of 65. Could this curve be a density curve for somevariable? Explain your answer.

Choose the correct answer below.

A.The curve could not be a density curve because the total area under the curve islessthan 1.

B.The curve could be a density curve because the total area under the curve isequalto 1.

C.The curve couldnot be a density curve because the total area under the curve isgreaterthan 1.

D. There is insufficient information to determine if this curve could be a density curve for some variable.

A variable is normally distributed with mean 6 and standard deviation 2.

a. Determine the quartiles of the variable.

b. Obtain and interpret the 90th percentile.

c. Find the value that65% of all possible values of the variable exceed.

d.Find the two values that divide the area under the corresponding normal curve into a

middle area of 0.95 and two outside areas of 0.025. Interpret the answer.

A. Q1= ? Q2= ? Q3= ?

What is a densitycurve?

Choose the correct answer below.

A.A density curve of a variable is any type of curve which represents the distribution of the variable.

B.A density curve of a variable is a smooth curve with which one can identify the shape of the distribution of the variable.

C.A density curve of a variable represents the approximate distribution of a continuous variable.

D.A density curve of a variable represents the distribution of a discrete variable.