9514 1404 393
Answer:
- $0.04 per cubic foot
- c(w) = 0.04w +80
- 3400 cubic feet
Step-by-step explanation:
(a, b) We are given two pairs of values:
(w, c) = (1900, 156) and (2600, 184)
so we can write the equation of the relationship using the 2-point form of the equation of a line.
y = (y2 -y1)/(x2 -x1)(x -x1) +y1
c = (184 -156)/(2600 -1900)(w -1900) +156 . . . . . substitute given points
c = 28/700(w -1900) +156
c(w) = 0.04w +80
The charge per cubic foot is $0.04.
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(c) For a bill of $216, the amount of water used is ...
216 = 0.04w +80
136 = 0.04w
3400 = w
Use of 3400 cubic feet of water would lead to a bill of $216.
