COMPLETE QUESTION:
Find some means. Suppose that X is a random variable with mean 30 and standard deviation 4. Also suppose that Y is a random variable with mean 50 and standard deviation 8. Find the mean of the random variable Z for each of the following cases. Be sure to show your work.
a) Z = 35-10X
b) Z = 12X-5
c) Z = X+Y
d) Z = X-Y
e) Z = 2X+2Y
Answer:
a) -265
b) 355
c) 80
d) -20
e) 40
Step-by-step explanation:
The attachment below contains the whole calculations that provides for the answers above
$897 is your correct answer because 5% of 900 is 3 so take away 3 from 900
(a) m = 
calculate the slope (m) using the ' gradient formula '
m = 
let (x₁, y₁) = (8, 9) and (x₂, y₂) = ( - 2, 4)
m =
=
= 
(b) y - 9 =
(x - 8)
the equation of a line in ' point- slope form ' is
y - b = m(x - a)
where m is the slope and (a, b) a point on the line
choose any of the 2 given points for (a, b) → (8, 9)
y - 9 =
(x - 8) → " point- slope form"
(c) y =
x + 5
the equation of a line in ' slope-intercept form ' is
y = mc + c
where m is the slope and c the y-intercept
expand and simplify the point- slope equation
y - 9 =
x - 4
y =
x - 4 + 9
y =
x + 5 → " slope- intercept form"
The answer is 2/3. Since you need our denominator to be 3 just find a number that divides 12 three times. Since 12/4 is 3 you have your denominator and because you used 4 on the denominator you must do it on the numerator so 8/4 is 2.
I hope I helped!