Rounded what is 489291 rounded to the nearest hundred

When you answer this can you explain

Aparking garage charges $1.12 for the first hour and 0.50 for each additional hour. what is the maximum length of time tom can park in the garage if we wishes to play no more than $5.62

Alice is paying her bill at a restaurant. but tax on the cost of a male is 5%. she decides to leave a tip 20% of the cost of the meal plus the tax