Mindy earns income equal to 40% of her sales minus the shipping cost of her products. She wants her income to be at least $1,500 this month and calculates that her total shipping cost will be $48. This can be represented by the inequality 0.4 x − 48 ≥ 1 , 500 , where x represents the amount of her sales in dollars. What is the least amount of sales Mindy must have to ensure that her income is at least $1,500 this month?