The average age of residents in a large residential retirement community is 69 years with standard deviation 5.8 years. a simple random sample of 100 residents is to be selected, and the sample mean age of these residents is to be computed. the probability that the average age, of the 100 residents selected is less than 68.5 years is

Suppose i flip two identical coins. what is the probability that i get one head and one tail?

Each person in an it department of 25 people works on at least one of 3 major projects: system security, program implementation, platform development. 10 people work on system security, 13 work on program implementation, and 12 work on platform development. 4 people work on system security and platform development, 5 people work on program implementation and platform development, and 2 people work on all three projects. how many people work on system security and program implementation?

(60 points) explain this in detail