Answer:
After 10 years the cost will be $ 97.52.
Step-by-step explanation:
This problem requires us to calculate the cost of graphing after 10 years if inflation rate is two percent. This can easily be calculated by compounding present value of current cost at the rate of 2%. Detail calculation is given below.
FV= 80 (1+2%)^10
FV = $ 97.52
Answer: 3 liters for 1.89.
Step-by-step explanation:
1.89/3 = 0.63 per liter
6.90/ 10 = 0.69 per liter
She will spend 112.8
24 times 4.70 equals 112.8
Vertex: (-5,-2); parabola opens up;
General form of the equation for a vertical parabola opening up is:
y-k = a(x-h)^2; knowing that the vertex is at (-5,-2), we can write:
y+2 = a(x+5)^2. We need to find the value of the coefficient a.
From the graph we see that y is 10 when x is approx. -1 3/4 (or -7/4).
subst. these values into y+2 = a(x+5)^2, we get:
10 + 2 = a(-7/4 + 5)^2, or 12 = a(13/4)^2, or 1 = a(169/16).
Solving for a: a = 16/169 = 0.09, or approx 16/160, or 1/10. Unfortunately, this is not close to any of the four answer choices.
I thought it best to try again, and fortunately my second try was correct:
10+2 = a(13/4)^2, or (169/16)a. Thus, 12 = a(169/16)
12
Solving for a: a = ------------- = 1.14. The answer choice closest to this is 1.
169/16
Answer A is correct.
