Answer:
a. Acct. receivable % uncollectible Est. uncollectible
1-30 days old $63,000 3% $1,890
31-90 days old $12,000 14% $1,680
> 90 days old $5,000 37% $1,850
Total $5,420
b. Date General journal Debit Credit
Dec 31 Bad debts expenses $5,150
Allowance for doubtful accounts $5,150
($5,420 - $270)