Fun time cruise line offers nightly dinner cruises departing from several cities on the East Coast on the United States, including Charleston Baltimore and Alexandria dinner cruise tickets sell for $50 per passenger fun time cruise lines, variable cost of providing a dinner is $30 per passenger and the fix cost of operating the vessels is $210,000 per month the companies relevant range extends to 20,000 monthly passengers if one time cruise line sells an additional 700 tickets by what amount will its operating income increase or operating loss decrease