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Modulo10 CheckDigit Calculation

The field entered is 735183. The last digit (3) is the check‑digit. The actual data value is 73518. The units digit and each alternating digit to the left of the units digit are treated as one number and are referred to as the odd‑digits number. In this example, the odd‑digits number is 758.

1. CA Ideal multiplies the odd‑digits number by 2 (758 x 2 = 1516).
2. CA Ideal adds together the individual digits in the product with the even digits (3 and 1) in the original data value (1 5 1 6 3 1 = 17).
3. CA Ideal subtracts the sum (17) from the next higher number ending in zero (20). In the example, this step is 20 ‑ 17 = 3.

Thus, the complete check‑digit field is 735183.