Bhavik bought 3 liters of milk and 5 loaves of bread for a total of $11. A month later he bought 4 liters of milk and 4 loaves of bread at the same price for a total of $10. How much does a liter of milk cost and how much does a loaf of bread cost?
Accepted Solution
A:
Let the price of 1 liter of milk be m, and let the price of 1 loaf of bread be b.
3 liters of milk cost 3m. 5 loaves of bread cost 5b. The total is $11. That gives us the first equation:
3m + 5b = 11
4 liters of milk cost 4m. 4 loaves of bread cost 4b. The total is $10. That gives us the second equation:
4m + 4b = 10
We have a system of two equations.
3m + 5b = 11 4m + 4b = 10
Multiply the first equation by -4. Multiply the second equation by 3. Then, add the equations.