Mean:
E[Y] = E[3X₁ + X₂]
E[Y] = 3 E[X₁] + E[X₂]
E[Y] = 3µ + µ
E[Y] = 4µ
Variance:
Var[Y] = Var[3X₁ + X₂]
Var[Y] = 3² Var[X₁] + 2 Covar[X₁, X₂] + 1² Var[X₂]
(the covariance is 0 since X₁ and X₂ are independent)
Var[Y] = 9 Var[X₁] + Var[X₂]
Var[Y] = 9σ² + σ²
Var[Y] = 10σ²
For the last question
40*3=120 total cakes
120*.15=18 chocolate cakes
Answer:
Hello,
p=4
q=7
Step-by-step explanation:
The vertex of the parabola is (-2,3)
Equation of the parabola is k(x+2)²+3=x²+px+q
Let's identify the coefficients:
kx²+4kx+4k+3=x²+px+q
so
k=1
4*1=p
4*1+3=q
Answer:
E
Step-by-step explanation:
The maximum of the data set is the point to the far right.
Point E is the maximum
Point A is the minimum
Point C is the mean
Answer:
12
Step-by-step explanation:
