Answer:
x=3
Explanation: 11-5=6
6/2= 3
Plug 3 into the equation and you get 2x3+5=11 which 2x3=6 and 6+5=11
Answer:
a) E(X)=1
b) σ=1
c) P(X>1)=0.368
d) P(2<X<5)=0.128
Step-by-step explanation:
We have X: "the time between two successive arrivals at the drive-up window of a local bank", exponentially distributed with λ = 1.
a) We have to compute the expected time between two successive arrivals.
The expected value for X as it is exponentially distributed is:

b) We have to compute the standard deviation of X.
The standard deviation is calculated as:

c) The probability that X is larger than 1 (P(X>1))
We can express the probability as:

d) The probability that X is between 2 and 5 (P(2<X<5))

Don’t you have to flip the sign when you divide by a negative? So I think she’s wrong bc the answer should be d is less than or equal to 7.5
Answer: 12a=48
Step-by-step explanation:
4a+6b=10
4a=10-6b
a=(10-6b)/4
a=(5-3b)/2
2a-4b=12
2((5-3b)/2)-4b=12
(5-3b)-4b=12
5-7b=12
-7b=7
b=-1
2a-4b=12
2a-4(-1)=12
2a+4=12
2a=8
a=4
a=4, b=-1
12a=48