Armando has a credit card that uses the adjusted balance method. For the first 10 days of one of his 30-day billing cycles, his balance was $2500. He then made a payment of $1600, so his balance decreased to $900, and it remained that amount for the next 10 days. Armando then made a purchase for $1300, so his balance for the last 10 days of the billing cycle was $2200. If his credit card's APR is 33%, how much was Armando charged in interest for the billing cycle?