Answer: The answer is just 3 people will get BOTH the free drink and free sandwich.
Step-by-step explanation:
Every 8th = 1 free drink
Every 28th = 1 free sandwich
200 costumers showed
Add 28 to 28 until you reach the closest to 200 so: 28,56,84,112,140,168,196
Then add 8 to 8 until 200, every number that match the 28th sequence is 1 costumer that receives 1 drink and 1 sandwich
The match numbers are 56,112,168