Final answer:
An error in recording a check on the bank reconciliation would decrease the bank balance.
Step-by-step explanation:
An error in recording a check on the bank reconciliation would decrease the bank balance because it means that the check was not included in the bank's records. This would result in an inaccurate bank balance on the reconciliation statement. To fix this error, the amount of the check should be deducted from the bank balance on the reconciliation statement.