Answer:
Jake can use 19.70 ccf to not exceed $ 64.00 in water bill.
Step-by-step explanation:
The cost function of water bill is:
[tex]C = C_{f}+C_{v}[/tex]
Where:
[tex]C_{f}[/tex] - Fix costs, measured in USD.
[tex]C_{v}[/tex] - Variable costs, measured in USD.
The fix and variable costs are, respectively:
[tex]C_{f} = 24.60[/tex]
[tex]C_{v} =2\cdot \left(\frac{Q}{100} \right)[/tex]
Where [tex]Q[/tex] is the water capacity consumed within a month, measured in cubic feet. Therefore, first formula is expanded:
[tex]C = 24.60+2\cdot \left(\frac{Q}{100} \right)[/tex]
If [tex]C = 64\,USD[/tex], the maximum water capacity is:
[tex]64 = 24.60+2\cdot \left(\frac{Q}{100} \right)[/tex]
[tex]39.40 = 2\cdot \left(\frac{Q}{100} \right)[/tex]
[tex]Q = 1970\,ft^{3}[/tex]
Which is equivalent to 19.70 ccf.
