Credit Card Check Digit Algorithm

Dr. K guides students through calculating a check digit on a credit card using a specific algorithm. The video covers the multiplication pattern, introduces 'funny math' for summing digits, and demonstrates shortcuts to find the check digit. The session concludes with a reveal of the correct check digit, emphasizing the fun and year-round nature of learning math.

What is the main goal of Dr. K's video lesson?

• To make students math geniuses

• To explain the history of credit cards

• To teach students how to cook

• To discuss summer vacation plans

What is a check digit used for in credit cards?

• To set the card's spending limit

• To determine the cardholder's name

• To verify the card's authenticity

• To calculate the card's expiration date

What is the first digit of a VISA credit card number?

• 6

• 3

• 4

• 5

What pattern is used in the algorithm for calculating the check digit?

• 4, 1, 4, 1

• 1, 3, 1, 3

• 2, 1, 2, 1

• 3, 2, 3, 2

What is the result of multiplying 4 by 2 in the credit card algorithm?

• 6

• 8

• 10

• 12

In the 'funny math' algorithm, what do you do with a product like 18?

• Subtract the digits

• Multiply the digits

• Add the digits

• Divide the digits

What is the next step after summing the digits in the algorithm?

• Find the next multiple of 20

• Find the next multiple of 15

• Find the next multiple of 10

• Find the next multiple of 5

What is the check digit revealed at the end of the video?

• 4

• 3

• 5

• 2