Bri goes to the movies and buys three items that together sum to $11.50. Two of the items she bought cost $3 each. Write an equation to express how much money Bri spent at the movies.

Martha is training for a duathlon, which includes biking and running. she knows that yesterday she covered a total distance of over 55.5 miles in more than than 4.5 hours of training. martha runs at a speed of 6 mph and bikes at a rate of 15.5 mph.