Answer:The mean number of checks written per day = 0.3370
The standard deviation = 0.5805
The variance = 0.3370
Step-by-step explanation:
Let the random variable x represent the number of checks he wrote in one day.
Given : The number of checks written in last year = 123
Let the number of days in the year must be 365.
Now, the mean number of checks written per day will be :-

We know that in Poisson distribution , the variance is equals to the mean value .


Thus, Standard deviation = 0.5805
Answer:
x = 0
y = -4
negative 4 cuz the line goes down, meaning it's negative
3+(-4)=(-1)
so, 3 is the missing number
Answer:
all work is shown/pictured
Answer:
I'm too tired to explain, here's some digital work on a site called Symbolab: