What is a real world situation for 15 +c= 17.50

All you need to do is make c =  2.50.

Mike has 15 dollars in his pockets when he started his walk, and when returned home his pockets now had $17.50. How much money did Mike pick up on the walk?

Mike is buying $17.50 worth of items from the store. He only has $15 with him, how much more does he need?

Hope this helps!

331.5? I think. So, 2 percent of 325, 6.5 6.5 + 325°.