Official Solution: The parking fee at a certain lot is $1.00 for the first 2 hours, plus $0.25 for each additional hour or fraction of an hour beyond the first 2 hours. Did the car remain parked for more than 12 hours at the parking lot? For any time exceeding 2 hours, the fee is calculated as \(1 + (⌈x⌉ - 2) * 0.25\), where \(⌈x⌉\) denotes the least integer greater than or equal to \(x\). The phrase "for each additional hour or fraction of an hour" means that if a car is parked for, say, 2.1 hours, it is rounded up and assumed to have been parked for 3 hours. Thus:
• If \(10 < x ≤ 11\), the fee would be \(1 + (11 - 2) * 0.25 = $3.25\).
• If \(11 < x ≤ 12\), the fee would be \(1 + (12 - 2) * 0.25 = $3.50\).
• If \(12 < x ≤ 13\), the fee would be \(1 + (13 - 2) * 0.25 = $3.75\).
Assuming the car was parked for \(t\) hours, the question asks whether \(t\) > 12.
(1) The total parking fee would have been $3.75 if the car had stayed 30 minutes longer.
This implies:
\(12 < t + 0.5 ≤ 13\)
\(11.5 < t ≤ 12.5\)
Not sufficient.
(2) The total parking fee would have been $3.25 if the car had stayed 90 minutes less.
This implies:
\(10 < t - 1.5 ≤ 11\)
\(11.5 < t ≤ 12.5\)
Not sufficient.
(1) + (2) Both statements provide the exact same information: \(11.5 < t ≤ 12.5\). Thus, even when combined, we still cannot determine if \(t > 12\). Not sufficient.
Answer: E