Double-subscript notation for decision variables should be ...

[formula1]

Double-subscript notation for decision variables should be avoided unless the number of decision variables exceeds nine.
  Indicate whether the statement is true or false

Question 2

A sample of 81 account balances of a credit company showed an average balance of 1,200 . The population standard deviation is 126 . You want to determine if the mean of all account balances is significantly different from 1,150 . Use a .05 level of significance.

[samiel-sayed]

Answer to Question 1

F

Answer to Question 2

H0:  = 1150
Ha:   1150 z = 3.57; therefore, reject H0 . There is sufficient evidence at  = .05 to conclude that the mean of all account balances is significantly different from 1,150.

[formula1]

Excellent

[bassamabas]

TYSM