Question

One tray holds eight sandwiches if there are 30 sandwiches in all, how many trays are needed?

Answer 1

Well 1 tray = 8 sandwiches
8/30 sandwiches 
2 trays = 16 sandwiched
3 trays = 24 sandwiches
4 trays = 32 sandwiches
you would need 4 trays.
I hope this helps you! =) 

Answer 2

30/8=3.75
So, you need 4 trays, since you can't have 75% of a tray.
Hope this helps