Answer:
a)= 2
b) 6.324
c) P= 0.1217
Step-by-step explanation:
a) The mean of the sampling distribution of X`1- X`2 denoted by ux`-x` = u1-u2 is equal to the difference between population means i.e = 2 ( given in the question)
b) The standard deviation of the sampling distribution of X`1- X`2 ( standard error of X`1- X`2) denoted by σ_X`1- X`2 is given by
σ_X`1- X`2 = √σ²/n1 +σ²/n2
Var ( X`1- X`2) = Var X`1 + Var X`2 = σ²/n1 +σ²/n2
so
σ_X`1- X`2 =√20 +20 = 6.324
if the populations are normal the sampling distribution X`1- X`2 , regardless of sample sizes , will be normal with mean u1-u2 and variance σ²/n1 +σ²/n2.
Where as Z is normally distributed with mean zero and unit variance.
If we take X`1- X`2= 0 and u1-u2= 2 and standard deviation of the sampling distribution = 6.324 then
Z= 0-2/ 6.342= -0.31625
P(-0.31625<z<0)= 0.1217
The probability would be 0.1217
Answer:
d. 5
Step-by-step explanation:
it just is trust me
Answer is A. 18
EXPLANATION-
Its Simplifying
(9x + -44) = (6x + 10)
Reorder the terms:
(-44 + 9x) = (6x + 10)
Remove parenthesis around (-44 + 9x)
-44 + 9x = (6x + 10)
Reorder the terms:
-44 + 9x = (10 + 6x)
Remove parenthesis around (10 + 6x)
-44 + 9x = 10 + 6x
Solving
-44 + 9x = 10 + 6x
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '-6x' to each side of the equation.
-44 + 9x + -6x = 10 + 6x + -6x
Combine like terms: 9x + -6x = 3x
-44 + 3x = 10 + 6x + -6x
Combine like terms: 6x + -6x = 0
-44 + 3x = 10 + 0
-44 + 3x = 10
Add '44' to each side of the equation.
-44 + 44 + 3x = 10 + 44
Combine like terms: -44 + 44 = 0
0 + 3x = 10 + 44
3x = 10 + 44
Combine like terms: 10 + 44 = 54
3x = 54
Divide each side by '3'.
x = 18
Simplifying
x = 18
