Answer: 41 hours
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Step-by-step explanation:
x = number of hours
y = total cost
The equation is y = 25x+250 since 250 is the initial cost, aka y intercept, and 25 is the slope telling us how much the cost goes up per hour (aka rate of change).
I recommend making a table of values to help see how/why that equation works out.
Plug in y = 1275 and isolate x.
y = 25x+250
1275 = 25x+250
1275-250 = 25x
1025 = 25x
25x = 1025
x = 1025/25
x = 41 hours
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Check:
If the customer rents the car for 41 hours, then they pay 25*41 = 1025 dollars on top of the initial fee of $250.
The total cost is therefore 1025+250 = 1275 dollars to confirm the answer.
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Extra info:
41 hours = 24 hours + 17 hours = 1 day + 17 hours
41 hours = 41/24 = 1.70833 days approximately