Answer:
a) 3.6
b) 1.897
c)0.0273
d) 0.9727
Step-by-step explanation:
Rabies has a rare occurrence and we can assume that events are independent. So, X the count of rabies cases reported in a given week is a Poisson random variable with μ=3.6.
a)
The mean of a Poisson random variable X is μ.
mean=E(X)=μ=3.6.
b)
The standard deviation of a Poisson random variable X is √μ.
standard deviation=S.D(X)=√μ=√3.6=1.897.
c)
The probability for Poisson random variable X can be calculated as
P(X=x)=(e^-μ)(μ^x)/x!
where x=0,1,2,3,...
So,
P(no case of rabies)=P(X=0)=e^-3.6(3.6^0)/0!
P(no case of rabies)=P(X=0)=0.0273.
d)
P(at least one case of rabies)=P(X≥1)=1-P(X<1)=1-P(X=0)
P(at least one case of rabies)=1-0.0273=0.9727
Answer:
(8, 2 )
Step-by-step explanation:
Given the 2 equations
x + 4y = 16 → (1)
- x + 3y = - 2 → (2)
Adding the 2 equations term by term will eliminate the x- term
0 + 7y = 14
7y = 14 ( divide both sides by 7 )
y = 2
Substitute y = 2 into either of the 2 equations and solve for x
Substituting into (1)
x + 4(2) = 16
x + 8 = 16 ( subtract 8 from both sides )
x = 8
solution is (8, 2 )
Answer:14
Step-by-step explanation:
1. Ratio : 2:3
2. Multiply the number of juniors by the Ratio
(2/3)(21)
3. Solve for answer
Answer: 14