请教数学题

alan19710811

1. What is the median number of employees assigned per project for the projects at Company Z? 

(1)   25 percent of the projects at Company Z have 4 or more employees assigned to each project.

(2) 35 percent of the projects at Company Z have 2 or fewer employees assigned to each project.

                  

A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.

B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.

C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

D. EACH statement ALONE is sufficient.

E. Statements (1) and (2) TOGETHER are NOT sufficient.

2.  If x < 0, then Ö(-x ·½x½) is

 

A.     -x

B.     -1

C.     1

D.     x

E.      Öx

答案是A，我怎么觉得A和D都有可能呀。比如X是-2的话，答案是2和-2呀。

3. How many seconds will it take for a car that is traveling at a constant rate of 45 miles per hour to travel a distance of 22 yards?    (1 mile = 1,160 yards)

 

A.     8

B.     9

C.     10

D.     11

E.      12

答案是C，可我怎么算都是22/14.5=1.5呀

4. If n is a positive integer and r is the remainder when (n-1)(n+1) is divided by 24, what is the value of r?

(1)     2 is not a factor of n.

(2)     3 is not a factor of n.

                  

A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.

B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.

C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

D. EACH statement ALONE is sufficient.

E. Statements (1) and (2) TOGETHER are NOT sufficient.

5.  Last year the price per share of Stock X increased by k percent and the earnings per share of Stock X increased by m percent, where k is greater than m.  By what percent did the ratio of price per share to earnings per share increase, in terms of k and m?

 

A.     k/m %

B.     (k-m) %

C.     [100(k-m)]/(100+k) %

D.     [100(k-m)]/(100+m) %

E.      [100(k-m)]/(100+k+m) %

6.  If M is the least common multiple of 90, 196, and 300, which of the following is NOT a factor of M?

 

A.     600

B.     700

C.     900

D.     2,100

E.      4,900

多谢好心同学帮忙指点呀！

alan19710811

求帮助呀！