Find the 90th percentile. What will be an ideal ...

[biggirl4568]

Find the 90th percentile.
 
  What will be an ideal response?

Question 2

The irregular component of a time series exhibits a tendency to grow or decrease rather steadily over long periods of time.
 
  Indicate whether the statement is true or false

[stillxalice]

Answer to Question 1

Find x0 such that P(X  x0 ) = 0.90 = P(Z  z0 ).
Since the area to the left of z0 is greater than 0.5, z0 must be larger than zero such that P(0 < Z < z0 ) = 0.40, so z0 = 1.28. Thus, x0 = 75 + (1.28 )(4 ) = 80.12

Answer to Question 2

FALSE

[biggirl4568]

Thanks for the timely response, appreciate it

[juliaf]

TYSM