Answer: he needs to work for 7 hours.
Explanation:
Let x represent the number of hours that he need to work to have $220 in his bank account.
Julio has $127 in his bank account. He gets $30 for his birthday. Since the total amount he wants to have in his bank account is 220, it means that the remaining amount he needs to save is
220 - (127 + 30) = 63
He also has a part-time job that pays $9 per hour. It means that the amount that he would earn if he works for 9 hours is 9x. Therefore,
9x = 63
x = 63/9
x = 7