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
Answer:
23 Girls
Step-by-step explanation:
23 plus 13 equals 36 and 23 is 10 more than 13.
Answer:
B(-6, 0)
Step-by-step explanation:
You want to find B such that ...
(B -A) = (3/4)(C -A) . . . . the required distance relation
4(B -A) = 3(C -A) . . . . . . multiply by 4
4B = 3C +A . . . . . . . . . . add 4A, simplify
Now, we can solve for B and substitute the given coordinates:
B = (3C +A)/4 = (3(-6, -2) +(-6, 6))/4 = (-24, 0)/4 = (-6, 0)
The coordinates of point B are (-6, 0).
Hope it helped u if yes mark me BRAINLIEST!
Tysm!
:D
Is there a image supposed to be attached?
Answer:
x=4.875
y=-0.25
Step-by-step explanation:
4x – 2y = 10
2x-y=10
y=2x-10
4x + 6y = 18
2x+3(2x-10)=9
8x=39
x=4.875
y=2(4.875)-10
y=-0.25
