How can i change 12/15 into decimal

The total cost of anja’s trip to the dentist was $628.35. she paid a flat fee of $89.95 which included the checkup and cleaning and then had 4 cavities filled, each of which cost the same amount. which shows the correct equation and value of x, the cost of each cavity filling?

Ftara spends $219 a month for her car payment and she makes $3,200 a month, what percent of her monthly income is spent on her car payment?

Nicole is making carrot bread she needs 5 cups of carrots for 2 cups of sugar.what is the ratio of cups of sugar to cups of carrots that nicole will need? write the ration in three different ways