What is the process and solution the the equation 8/a 3=4/a-2?

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?

If sec theta = 5/3 and the terminal point determined by theta is in quadrant 4, then

You are at a restaurant and owe $38 for your meal. you want to leave a 20% tip. how much will your tip be?