請想問各位下列幾道數學題怎麼算出來的:
A certain holiday is always on the fourth Tuesday of Month X. If Month X has 30 days, on how many different dates of Month X can the holiday fall?
4, 5, 6, 7, 8
(D)
Part of a $10,000 inheritance was invested at 4% and the remainder was invested at 6%. The total simple annual interest earned on the $10,000 at the end of one year was $520. (這題題目我看不懂)
A: The amount invested at 4%
B: The amount invested at 6%
(B)
The vertices of square S have coordinates (-1, -2), (-1, 1), (2, 1), and (2, -2), respectively. What are the coordinates of the point where the diagonals of S intersect?
(B)
Sixty-eight people are sitting in 20 cars and each car contains at most 4 people. What is the maximum possible number of cars that could contain exactly 1 of the 68 people? (這題題目我看不懂)
2, 3, 4, 8, 12
(C)
If n is any prime number greater then 2, which of the following CANNOT be a prime number?
n-4, n-3, n-1, n+2, n+5
(E)
The "reflection" of a positive integer is obtained by reversing its digits. For example, 321 is the reflection of 123. The difference between a five-digit integer and its reflection must be divisible by which of the following?
2, 4, 5, 6, 9
(E)
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