Question

A data entry input control in which the application software sums the first four digits of a customer number to calculate the value of the fifth digit and then compares the calculated number to the number typed in during data entry is an example of a A)check digit verification. B)validity check. C)closed-loop verification. D)duplicate data check.

Answer 1

The control mechanism in the given scenario is known as check digit verification, used to ensure the accuracy of data entry for a customer number by comparing a calculated check digit against the entered one.

Step-by-step explanation:

The data entry control described in the question is a method for ensuring the accuracy of a customer number entered into an application. This control mechanism is known as check digit verification. It works by summing the first four digits of the customer number and using the sum to calculate the value of the fifth digit, which is the check digit. This calculated check digit is then compared to the one that was entered to verify the integrity of the customer number. If the two digits match, the number is considered valid; if they do not match, it's an indication that there may have been a data entry error.