Winter 2019, Assignment
2 Mary Gottfried
0622954
1. Indicate if the credit card number is valid and if it is not, what would the valid credit
card number be? Please show your work.
a.4550 2081 6375 1768
Starting with the second to the right digit, multiply by 2:
8_10_ 4_16_12_14_2_12
Add digits that have not been changed, if the multiplied digit is higher than 9, add the 2 digits to
get total sum:
8510 4071 3355 2738
Sum numbers:
8+5+1+0+4+7+1+3+3+5+5+2+7+3+8=62
This is not a valid credit card number because it is not divisible by 10. Need to change the check
digit to make the sum 60(subtract 2) or 70(add 8). The value on the far right is 8, adding 8
would create a digit greater than 9. Subtracting 2 makes the check digit 6.
The valid credit card number would
be: 4550 2081 6375 1766
b. 5491 3865 6189 8631
Using the same steps as before part a:
10_18_6_12_12_16_16_6
1491 6835 3179 7661
Sum of numbers=77
This is not a valid number. The sum needs to be divisible by 10. Change the check digit by
adding 3(to get 80) or subtracting 7(to get 70). 7 cannot be subtracted from 1, therefore, add 3
to the check number. The valid credit card number would be:
5491 3865 6189 8634
c. 4611 1153 6729 8795
Using the same steps as part
a: 8_2_2_10_12_4_16_18
This study source was downloaded by 100000861168648 from CourseHero.com on 04-18-2023 05:19:31 GMT -05:00
https://www.coursehero.com/file/72461277/Assignment-2-Computer-Crime-2750docx/
, 8621 2113 3749 7795
The sum is= 75
This is not a valid credit card number because it is not divisible by 10. The sum needs to be
80(add 5) or 70 (subtract 5). The check number cannot exceed 9, 5+5=10. Therefore, 5 must be
subtracted from 5. The valid credit card number would be:
4611 1153 6729 8790
d. 1234 5678 9098 7654
same steps as used previously:
2_6_10_14_18_18_14_10
2264 1658 9098 5614
The sum= 76
This is not a valid credit card number because it is not divisible by 10. The check number
cannot exceed 9. To get a sum divisible by 10, the sum needs to equal 80 (add 4) or 70
(subtract 6). 6- 4=-2, there cannot be negative numbers. Therefore, add 4, the valid credit card
number would be:
1234 5678 9098 7658
2. a) [3 marks] What do you see (cut and paste the details into your answer)? How could
good guys and bad guys make use of this information?
Kelly-Anne Kenny
Admin Name
Wal-Mart Canada Corp 1940
Admin Organization
Argentia Road
Admin Street
Mississauga
Admin City Admin State/Province
ON
Admin Postal Code
Admin Country
L5N1P9
CA
Admin Phone
+1.9058212111
Admin Phone Ext:
Admin Fax+1.9058216353
Admin Fax Ext:
Adminnetnames@wal-
Emailmart.com Registry Tech 24086965- IDCIRA
Tech NameKelly-Anne
This study source was downloaded by 100000861168648 from CourseHero.com on 04-18-2023 05:19:31 GMT -05:00
https://www.coursehero.com/file/72461277/Assignment-2-Computer-Crime-2750docx/
2 Mary Gottfried
0622954
1. Indicate if the credit card number is valid and if it is not, what would the valid credit
card number be? Please show your work.
a.4550 2081 6375 1768
Starting with the second to the right digit, multiply by 2:
8_10_ 4_16_12_14_2_12
Add digits that have not been changed, if the multiplied digit is higher than 9, add the 2 digits to
get total sum:
8510 4071 3355 2738
Sum numbers:
8+5+1+0+4+7+1+3+3+5+5+2+7+3+8=62
This is not a valid credit card number because it is not divisible by 10. Need to change the check
digit to make the sum 60(subtract 2) or 70(add 8). The value on the far right is 8, adding 8
would create a digit greater than 9. Subtracting 2 makes the check digit 6.
The valid credit card number would
be: 4550 2081 6375 1766
b. 5491 3865 6189 8631
Using the same steps as before part a:
10_18_6_12_12_16_16_6
1491 6835 3179 7661
Sum of numbers=77
This is not a valid number. The sum needs to be divisible by 10. Change the check digit by
adding 3(to get 80) or subtracting 7(to get 70). 7 cannot be subtracted from 1, therefore, add 3
to the check number. The valid credit card number would be:
5491 3865 6189 8634
c. 4611 1153 6729 8795
Using the same steps as part
a: 8_2_2_10_12_4_16_18
This study source was downloaded by 100000861168648 from CourseHero.com on 04-18-2023 05:19:31 GMT -05:00
https://www.coursehero.com/file/72461277/Assignment-2-Computer-Crime-2750docx/
, 8621 2113 3749 7795
The sum is= 75
This is not a valid credit card number because it is not divisible by 10. The sum needs to be
80(add 5) or 70 (subtract 5). The check number cannot exceed 9, 5+5=10. Therefore, 5 must be
subtracted from 5. The valid credit card number would be:
4611 1153 6729 8790
d. 1234 5678 9098 7654
same steps as used previously:
2_6_10_14_18_18_14_10
2264 1658 9098 5614
The sum= 76
This is not a valid credit card number because it is not divisible by 10. The check number
cannot exceed 9. To get a sum divisible by 10, the sum needs to equal 80 (add 4) or 70
(subtract 6). 6- 4=-2, there cannot be negative numbers. Therefore, add 4, the valid credit card
number would be:
1234 5678 9098 7658
2. a) [3 marks] What do you see (cut and paste the details into your answer)? How could
good guys and bad guys make use of this information?
Kelly-Anne Kenny
Admin Name
Wal-Mart Canada Corp 1940
Admin Organization
Argentia Road
Admin Street
Mississauga
Admin City Admin State/Province
ON
Admin Postal Code
Admin Country
L5N1P9
CA
Admin Phone
+1.9058212111
Admin Phone Ext:
Admin Fax+1.9058216353
Admin Fax Ext:
Adminnetnames@wal-
Emailmart.com Registry Tech 24086965- IDCIRA
Tech NameKelly-Anne
This study source was downloaded by 100000861168648 from CourseHero.com on 04-18-2023 05:19:31 GMT -05:00
https://www.coursehero.com/file/72461277/Assignment-2-Computer-Crime-2750docx/
