She can drink 3 x 5 = <<3*5=15>>15 boxes of milk during weekdays.
She can drink 3 x 2 = <<3*2=6>>6 boxes of milk on Saturdays.
She can also drink 3 x 3 = <<3*3=9>>9 boxes of milk during Sundays.
Therefore, Lolita can drink 15 + 6 + 9 = <<15+6+9=30>>30 boxes of milk per week.
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