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
92
given 2a² + 5b²
substitute given values for a and b into the expression
2(- 6)² + 5(2)² = (2 × 36 ) + (5 × 4) = 72 + 20 = 92
Given:
m = -8 degrees/hour, the rate of change of temperature
Let x = hours
Let y = temperature, °F
Then y = -8x + b
where b = constant
When x = 0, then y = b.
Therefore b = initial temperature
If the temperature drops by at least 36 °F in the next x hours, then
b - y(6) ≥ 36
b - (-8x + b) ≥ 36
8x ≥ 36
x ≥ 4.5 hours
Answer: At least 4.5 hours
Answer: 720
Step-by-step explanation: Hope this helps
Answer:
C is the answer
C ) y = 
Step-by-step explanation:
2 y - x = 
( -y + 1)
(2 y - x ) 4 = 3 ( -y +1)
8 y - 4 x = -3 y + 3
8 y + 3 y = 4 x + 3
11 y = 4 x + 3
∴ y = 
