At January 1, 2019, Betty DeRose, Inc. had accounts receivable totaling $250,000 and had an allowance for doubtful accounts with a $11,250 credit balance. During 2019, Betty reported sales revenue of $410,000, write-offs of $13,000, recoveries of $4,270, cash collections from customers of $322,000, and bad debt expense of $17,580. At December 31, 2019, Betty prepared the following aging schedule:

Accounts Receivable      % Uncollectible

not past due            $180,000                   2%

         1-30 days past due        45,000                   5%

         31-60 days past due       37,000                   ?

         61-90 days past due         ?                     12%

over 90 days past due     12,000                  40%

Calculate the percentage estimated to be uncollectible for the accounts receivable that are 31-60 days past due. Enter your answer as a number followed by the % symbol (i.e., 15%).