Gray Company has employed a bookkeeper who is inexperienced. On December 30, after reviewing the records for the year, you discover the following error. On May 1, Gray Company purchased Supplies on account, $940. The bookkeeper recorded this by debiting Supplies Expense for $490 and crediting Cash for $490. Note: Assume that it is the company's policy to record the purchase of supplies in the Supplies account. Required: Prepare a correcting entry on December 30. Make sure to enter the day for each separate transaction.