Valeria practices the piano 910 minutes in 5 weeks. Assuming she practices the same amount every week, how many minutes would she practice in 4 weeks?

If Valeria practices the piano 910 minutes in 5 weeks, then she practices 910/5 = <<910/5=182>>182 minutes per week.

Therefore, in 4 weeks, she would practice 4*182 = <<4*182=728>>728 minutes. Answer: \boxed{728}.