y = 56/2 x + 20
y = 28x + 20
Let's assume the number be x.
So, product of seven and a number can be written as 7*x.
Now the given statement is “One-fifth less than the product of seven and a number” which means we need to take out 1/5 from 7x. Hence, it can be converted into an algebraic expression as follows:

I believe the answer is Production Cost
0.07x+0.0825(9000-x)=706.25
Solve for x
X=2900 at 7%
9000-2900=6100 at 8.25%
Salad and pbj: 24 students
Turkey sandwich and school lunch: 30 students
30
-
24
---------
6