Answer:
9x^4 -36
Step-by-step explanation:
see image below:)
Answer:
42 acres to 72 acres, there is an increase of 30 acres
percentage wise
72-42=30
30/72=.4166...
therefore there is also a 41.6% increase
Step-by-step explanation:
71.42 Percentage change:×100%
Now, the change is given from 42 acres to 72 acres, therefore
Change= 72-42=30
⇒Percentage change= ×100%
= 71.42
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
Victoria is 9. Her neighbor is 5.
