Q:

Supposed a Visa card had a credit card number of 4162 0012 3456789a where a is the check number what is the check number? A) 0 B) 3 C) 9 D) 7

Accepted Solution

A:
Answer:Option B) 3Step-by-step explanation:we have the number4162 0012 3456 789aFind the value of a (check number)step 1Multiply every even-position digit (when counted from the right) in the number by two. If the result is a two digit number, then add these digits together to make a single digit4162 0012 3456 789a9(2)+7(2)+5(2)+3(2)+1(2)+0(2)+6(2)+4(2)(18)+(14)+(10)+(6)+(2)+(0)+(12)+(8)Remember that If the result is a two digit number, then add these digits together to make a single digitso(1+8)+(1+4)+(1+0)+(6)+(2)+(0)+(1+2)+(8)(9)+(5)+(1)+(6)+(2)+(0)+(3)+(8)=34step 2 add every odd-position digit4162 00123456 789aso8+6+4+2+0+2+1=23step 3Adds  the result in step 1 and the result in step 234+23=57The check-digit is what number needs to be added to this total to make the next multiple of 10 In our case, we’d need to add 3 to make 60thereforeThe check number is 3