Question

You bought 12 one-gallon bottles of apple and orange juice for a school dance. the apple juice was on sale for $1.00 per one-gallon bottle. the orange juice was $1.75 per one-gallon bottle. you spend $15.00. how many bottles of each type of juice did you buy?

Answer 1

For this case we first define variables:
x: bottles of apple juice
y: bottles of orange juice
We write the system of equations:
x + y = 12
1x + 1.75y = 15
Solving the system of equations we have:
x = 8
y = 4
Answer:
you did buy:
8 bottles of apple juice
4 bottles of orange juice