A half-dollar coin issued by the United States Mint measures 30.61 millimeters across. Nick has 9 half dollars. He lines them up edge to edge in a row. What is the total length of the row of half dollars?

You coordinate volunteers for litter cleanup in local parks. your spreadsheet lists drivers and the number of seat belts in each driver’s car. the spreadsheet calculates the number of drivers (d) and the total number of seat belts (s). you want to know the maximum number of volunteers, besides drivers, that can be transported to the park in a single trip given that each person must have a seat belt of their own.