Answer:
a) Var[z] = 1600
D[z] = 40
b) Var[z] = 2304
D[z] = 48
c) Var[z] = 80
D[z] = 8.94
d) Var[z] = 80
D[z] = 8.94
e) Var[z] = 320
D[z] = 17.88
Step-by-step explanation:
In general
V([x+y] = V[x] + V[y] +2Cov[xy]
how in this problem Cov[XY] = 0, then
V[x+y] = V[x] + V[y]
Also we must use this properti of the variance
V[ax+b] = 
V[x]
and remember that
standard desviation = ![\sqrt{Var[x]}](https://tex.z-dn.net/?f=%5Csqrt%7BVar%5Bx%5D%7D)
a) z = 35-10x
Var[z] = 
Var[x] = 100*16 = 1600
D[z] = 
= 40
b) z = 12x -5
Var[z] = 
Var[x] = 144*16 = 2304
D[z] = 
= 48
c) z = x + y
Var[z] = Var[x+y] = Var[x] + Var[y] = 16 + 64 = 80
D[z] = 
= 8.94
d) z = x - y
Var[z] = Var[x-y] = Var[x] + Var[y] = 16 + 64 = 80
D[z] = = 8.94
e) z = -2x + 2y
Var[z] = 4Var[x] + 4Var[y] = 4*16 + 4*64 = 320
D[z] = 
= 17.88
It would be the 1st one ( 12in× 1in/2.5ft) the reason is you want the measurements to match so that way when you solve the equation you are multiply 12 by 2.5 to get the number of inches
Answer:
The Answer is 50
Step-by-step explanation:
The angle of the whole thing is 90 so subtract 40 from that
Answer: 8 pounds.
Explanation:
1) Let's start making clear the statement it is: " Mama Mia restaurant used 1/2 of their mozzarella cheese making pizza and the remaining 64 ounces making pasta. How many pounds of mozzarella cheese did Mama Mia start with? 1 pound = 16 ounces."
2) Since, 1/2 of the chesse was used to make pizza, the remaining part, which was used to make pasta, is 1 - 1/2 = 1/2.
3) Hence, you say that 1/2 of cheese equals 64 ounces, which means that Mama Mia started with 2 × 64 ounces, i.e. 128 ounces.
4) Now, use the conversion factor to convert 128 ounces to pound:
a) 1 pound = 16 ounces ⇒ 1 = 1 pound / 16 ounces
b) 128 ounces × 1 pound / 16 ounces = 8 pounds.
