Answer:
The smallest amount of cards he needs to buy is 80.
Step-by-step explanation:
What Eddie wants to find is the least common multiple. What a least common multiply is that you try to find the smallest number that both 5 and 16 go into.
Step 1: Find the LCM of 5 and 16
5 -> 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80
16 -> 16, 32, 48, 64, 80
Answer: The smallest amount of cards he needs to buy is 80.
