Answer:
2.625 cups or 21 ounces
Step-by-step explanation:
Ava needs 3/4 cup of blue paint for every 1 cup of white paint. So, the ratio is 0.75 : 1.
She has 28 ounces of white paint. But, you have to convert ounces to cups.
1 cup = 8 ounces
28 ounces ÷ 8 ounces/cup = 3.5 cups
Now set up a ratio.

X (how much blue paint is needed) is over 3.5 cups (the amount of white paint she has)
Cross multiply and divide.

x = 0.75 × 3.5
x = 2.625 cups
To convert to ounces, multiply by 8.
2.625 cups × 8 ounces = 21 ounces
Therefore, Ava needs 2.625 cups or 21 ounces of blue paint.
Hope that helps.
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 and explanation:
Null hypothesis: p is not 54%
Alternative hypothesis : p is equal 54%
First find standard deviation
Standard deviation is:
σ = √[ P ( 1 - P ) / n ] = √[ 0.54×0.46/220 ] =0.033
The z score is calculated p-P/σ = (0.54-0.50)/0.033 = 1.2121
Therefore we can conclude that proportions are not same and fail to reject the null hypothesis
Answer:
C = 13
Step-by-step explanation:
+
= 
+
= 169
= 13
X = 12 inches so D is correct