Assume that the cost of the milk is x. We are given that a sandwich costs 0.75$ more than the cost of milk. This means that: cost of sandwich = cost of milk + 0.75 cost of sandwich = x + 0.75
Now, the customer bought 4 sandwiches and 4 containers of milk at the cost of 7$. We will transform this into an equation as follows: total cost = cost of 4 sandwiches + cost of 4 containers of milk 7 = 4(x+0.75) + 4(x)
Solve the above equation to get x as follows: 7 = 4x + 3 + 4x 7-3 = 8x 8x = 4 x = 0.5
Therefore: cost of milk = x = $0.5 cost of sandwich = x+0.75 = 0.5+0.75 = $1.25
