The Test figure in a Credit Cards
Take a Visa Credit Card with the Number
0699 0043 1313 9642
Count the Separate figures, starting fRom the Right. The 2
Thus becomes the first figure and the 0 on the left the sixteenth. Now write down under the number
all figures in the odd positions:
0699 0043 1313 9642
6 9 0 3 3 3 6 2
Double The figures in the even postions and again enter the result below the original
NUmber. If the result of doubling a figure is greater than 9 , Subtract 9.
This gives us,
0699 0043 1313 9642
0699 0083 2323 9682
Now add the figure in the bottom line:
0 + 6 + 9 + 9 + 0 + 0 + 8 + 3 + 2 + 3 + 2 + 3 + 9 +
6 + 8 + 2
With a visa Card number, the result must be divisible by 10. In our case
the sum is 70, as it should be. The opposite does not apply. If a number divisible by 10 is obtained
it does not necessarily follow that the original number was a Visa Credit Card Number.
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