The price of the fries would be $2.50, the price of the drink would be $2.50, and the price of the cheeseburger wold be $7.50.
We can write a set of equations to represent the prices, if 'f' is fries, 'd' is drink, and 'c' is cheeseburger:
c = 3f
f = d
Using these equations, we can then write out the sum of the items also, as it would be c + f + d = 12.50, but as we know that c = 3f and d = f, we can write it as 3f + f + f = 12.50, and then solve:
3f + f + f = 12.50
5f = 12.50
÷ 5
f = $2.50
Now that we know the price of the fries, we know that the price of the drink is the same, so the drink is also $2.50. Then, we can multiply 2.50 by 3 as we know that the cheeseburger is 3 times the cost of the fries, and 2.50 × 3 = 7.50.
I hope this helps!
