Carpet Master would be cheaper because 6 x 9 would be 54 $$$
If the recipe makes enough stew for 6 people, and the ingredients cost $9.75, then for 24 people it will cost $x. You can write this statement as
6 people - $9.75,
24 people - $x.
Or as proportion,

Find x:

Answer: It would cost $39 to serve 24 people
Just watch videos on youtube.