Quantitative Reasoning

Hi,
can somebody explain it to me
Thanx in advance.

A certain company assigns employees to offices in such a way that some of the offices
can be empty and more than one employee can be assigned to an office. In how many
ways can the company assign 3 employees to 2 different offices?
A. 5
B. 6
C. 7
D. 8
E. 9

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The infinite sequence a1, a2,…, an,… is such that a1 = 2, a2 = -3, a3 = 5, a4 = -1, and an =
an-4 for n > 4. What is the sum of the first 97 terms of the sequence?
A. 72
B. 74
C. 75
D. 78
E. 80

and can somebody also give some link for basics of sequences.

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Which of the following fractions has a decimal equivalent that is a terminating decimal?
A.
189
10
B.
196
15
C.
225
16
D.
144
25
E.
128

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Company S produces two kinds of stereos: basic and deluxe. Of the stereos produced by
Company S last month,
3
2
were basic and the rest were deluxe. If it takes
5
7
as many
hours to produce a deluxe stereo as it does to produce a basic stereo, then the number of
hours it took to produce the deluxe stereos last month was what fraction of the total
number of hours it took to produce all the stereos?
6
A.
17
7
B.
31
14
C.
15
7
D.
35
17
E.
2
1

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Leo can buy a certain computer for p1 dollars in State A, where the sales tax is t1 percent,
or he can buy the same computer for p2 dollars in State B, where the sales tax is t2
percent. Is the total cost of the computer greater in State A than in State B?
10
(1) t1 > t2
(2) p1t1 > p2t2

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