At first, John had some money. He spent 1⁄4 of it on a T-shirt and 2⁄5 of the remainder on a pair of shoes. After that, his parents gave him $120. The ratio of the total amount of money he had at the end to the amount of money he had at first was 5 : 4. How much money did John have at first?
Online lesson with Teacher Felicia of Matrix Math @ Marine Parade.