Accounts Recievable Balance $34,825; Allowance for Bad Debt Balance $409
0-30 days = 20,000 = 5%
30-60 days = 10,000 = 20%
Over 60 days = Balance = 40%

I assumed that "Balance" meant the remaining amount of Acc./Rec. after 60 days. The adjusting entry I came up with was..
Bad Debt Expense 4,521
Allowance for Bad Debt 4,521
After this adjustment entry the balance on Allowance for Bad Debts would be $4,930.

1 20,000.00 0.05 1,000.00
2 10,000.00 0.20 2,000.00
3 4,825.00 0.40 1,930.00

34,825.00 4,930.00

The journal entry is 100% correct.