A runner's racecourse has a total distance of 7.5 mi. Race officials want to mark the course every 400 yd with a flag, including one at the finish line. (The starting line does not need a flag.) How many flags are needed? First fill in the blanks on the left side of the equation using three of the ratios shown. Then write your answer on the right side of the equation. 400 yd 1 flag 3 ft 1 yd 5280 ft 1 mi ft yd mi Ratios: 1 flag 400 yd 1 yd 3 ft I mi 5280 ft in flag 7.5 mi X X X = flags X