Answer:
μ ≈ 2.33
σ ≈ 1.25
Step-by-step explanation:
Each person has equal probability of ⅓.
The mean is the expected value:
μ = E(X) = ∑ X P(X)
μ = (1) (⅓) + (2) (⅓) + (4) (⅓)
μ = ⁷/₃
The standard deviation is:
σ² = ∑ (X−μ)² P(X)
σ² = (1 − ⁷/₃)² (⅓) + (2 − ⁷/₃)² (⅓) + (4 − ⁷/₃)² (⅓)
σ² = ¹⁴/₉
σ ≈ 1.25
Answer:
In the account that paid 6% Susan invest
In the account that paid 5% Susan invest
Step-by-step explanation:
we know that
The simple interest formula is equal to
where
I is the Final Interest Value
P is the Principal amount of money to be invested
r is the rate of interest
t is Number of Time Periods
Part a) account that paid 6% simple interest per year
in this problem we have
substitute in the formula above
Part b) account that paid 5% simple interest per year
in this problem we have
substitute in the formula above
we know that
substitute and solve for x
therefore
In the account that paid 6% Susan invest
In the account that paid 5% Susan invest