12. Tanisha, a manager at a state park, counted the money in the cash register at the end of her shift, and then she deposited the money in the bank. When she went back to her office, she accidentally shredded the deposit slip. She remembered that there were only $5 and $ 10 bills. She also recalled that there were 27 bills totaling $205. How many $5 bills were in Tanisha's cash register at the end of her shift?