Oki so plz and show proof or evidence

The last time i bought this product , it cost $20.00 but it looks like it cost 29. 60 today? what is the increase

Need ! the total ticket sales for a high school basketball game were $2,260. the ticket price for students were $2.25 less than the adult ticket price. the number of adult tickets sold was 230, and the number of student tickets sold was 180. what was the price of an adult ticket?

Yvaries inversely as x. y =12 when x=5. find y when x=4