The shirts she bought cost her $20 because 2 x 10 = <<2*10=20>>20
She earned $50 selling her clothes because 20 + 30 = <<20+30=50>>50
She made $15 off pants because 3 x 5 = <<3*5=15>>15
She made 15 dollars from shorts because 3 x 5 = <<3*5=15>>15
She made $20 off shirts because 50 - 15 - 15 = <<50-15-15=20>>20
She sold 5 shirts because 20 / 4 = <<20/4=5>>5
#### 5