You can 14 rows of 5 chairs, which also means you can do 5 rows of 14. Or 7 rows of 10 or 10 rows of seven. That's all I'm getting that doesn't exceed the 20 row limit.
Explanation - 56 is what you start out with. you will need to find 25% of those 56 to see the remaining. So 25% of 56 is 14 because .25 x 56 is 14. You then subtract 56 from the 14 Tuna sandwiches and you’re left with 42.
