Use reasoning to lead to the answer of the following question:
George is about to celebrate his 25th birthday. Since his 15th birthday, he's been given a special $1 bill from his parents. They told him that on his 25th birthday, for every bill he still has, they will give him $1.5 in exchange. He spent 20% of his special bills. How much will he receive from his parents when he exchanges them?

12
He received 10 special bills because 25 - 15 = 10.

He has 80% of them left because 100 - 20 = 80.

He has 8 left because 10 x.

8 = 8.

His parents will give her $12 for them because 8 x 1.

5 = 12.

.

The answer is 12