Answer:x is 15
Step-by-step explanation:
Answer:
1276.19553 
Step-by-step explanation:
First, find height using Pythagoras thorem.
a=
a=15.61
Then use the formula to find the surface area of a cone.
π•12.5•(12.5+
)=1276.19553 
Answer: The mean number of checks written per day 
Standard deviation
Variance 
Step-by-step explanation:
Given : The total number of checks wrote by person in a year = 126
Assume that the year is not a leap year.
Then 1 year = 365 days
Let the random variable x represent the number of checks he wrote in one day.
Then , the mean number of checks wrote by person each days id=s given by :-

Since , the distribution is Poisson distribution , then the variance must equal to the mean value i.e. 
Standard deviation : 