Each day that a library book is kept past its due date, a $0.30 fee is charged at midnight. Which ordered pair is a viable solution if x represents the number of days that a library book is late..? 

Each day that a library book is kept past its due date, a $0.30 fee is charged at midnight. Which ordered pair is a viable solution if x represents the number of days that a library book is late and y represents the total fee?

A. (–3, –0.90)

B. (–2.5, –0.75)

C. (4.5, 1.35)

D. (8, 2.40)

Answer:

Given the conditions, we can eliminate the ordered pairs with negative x-values since they represent scenarios where the book is returned early, not late. Therefore, we can disregard (–3, –0.90) and (–2.5, –0.75).

Regarding the ordered pair (4.5, 1.35), it's important to note that the fee is charged at midnight, so if the book is 4.5 days late, it incurs the fee for 4 days late, not 5 days. Therefore, the fee for 4.5 days late would be the same as for 4 days late, which is $1.20, not $1.35. Thus, (4.5, 1.35) is not a valid solution.

Finally, for (8, 2.40), when the book is 8 days late, the total fee would be 8×0.30=2.40, which matches the given y-value in the ordered pair. Therefore, (8, 2.40) is indeed the correct solution.

Linear Equations and their Applications

Linear equations are mathematical expressions that describe relationships between variables where each term is either a constant or a product of a constant and a variable raised to the first power. They take the form: ax + by = c. Where a, b, and c are constants, and x and y are variables. Linear equations are fundamental in mathematics and have various applications across different fields:

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