Will give brainliest again. Lol

Shiny white dental insurance costs $258 per year. approximately one-third of insured people need a filling, which averages $110 each. 80% of insured people get a preventive check-up each year, and the average cost of this visit is $95. if you consider shiny white’s income and expenses, what is the expected value of each insured customer?

What is the standard deviation of the following data set rounded to the nearest tenth? 3, 17, 18, 15, 12, 21, 9

Explain how you can find the missing fraction in 3 4/5 / (blank) 2 5/7. then find the missing fraction.