Respuesta :
Answer:
One granola costs $1.40.
One water bottle costs $0.75.
Step-by-step explanation:
This question can be solved by a simple system of equations.
I am going to say that
x is the cost of each granola bar.
y is the cost of each bottle of water.
The first step is building the system:
10 granola bars and twelve bottles of water cost $23.
This means that:
10x + 12y = 23.
5 granola bars and 4 water bottles of water of water cost $10
This means that:
5x + 4y = 10
So we have to solve the following system of equations:
10x + 12y = 23
5x + 4y = 10
I am going to multiply the second equation by -2, and use the addition method. So:
10x + 12y = 23
-10x - 8y = -20
10x - 10x + 12y - 8y = 23 - 20
4y = 3
y = 0.75
y = 0.75 means that each water bottle costs 75 cents.
5x + 4y = 10
5x = 10 - 4y
5x = 10 - 4*0.75
5x = 7
x = 1.4.
x = 1.4 means that each granola costs $1.40.
Answer:one granola costs $1.4
One bottle of water costs $0.75
Step-by-step explanation:
Let x represent the cost of one granola.
Let y represent the cost of one water bottle.
10 granola bars and twelve bottles of water cost $23. It means that
10x + 12y = 23 - - - - - - - - - - - 1
5 granola bars and 4 water bottles of water of water cost $10. It means that
5x + 4y = 10 - - - - - - - - - - - 2
Multiplying equation 1 by 1 and equation 2 by 2, it becomes
10x + 12y = 23
10x + 8y = 20
Subtracting, it becomes
4y = 3
y = 3/4 = 0.75
Substituting y = 0.75 into equation 1, it becomes
10x + 12 × 0.75 = 23
10x + 9 = 23
10x = 23 - 9 = 14
x = 14/10 = 1.4
