Sandy Company Uses Both Special Journals and a General Journal

Essay

Sandy Company uses both special journals and a general journal. The company accountant made the following errors during July.
1. Incorrectly added the credit entries in a customer's account in the accounts receivable subsidiary ledger. The total was listed as $2,690; it should have been $2,790.
2. A remittance of $400 from Tom Short was correctly recorded in the cash receipts journal, but the amount was posted incorrectly to the account of customer Will Short in the subsidiary ledger.
3. A purchase of merchandise on account from Easton Company for $1,000 was incorrectly entered in the purchases journal at $10,000.
4. In the sales journal, the entries were incorrectly added for the month. The monthly total was listed as $21,620; it should have been $21,260.
Instructions
Indicate how each of the above errors might be discovered.