几道GWD MATH求解

cathyyan

    

求解题思路：

Six cards numbered from 1 to 6 are placed
in an empty bowl.  First one card is
drawn and then put back into the bowl; then a second card is drawn.  If the cards are drawn at random and if the
sum of the numbers on the cards is 8, what is the probability that one of the
two cards drawn is numbered 5 ?

    

 

    

A.    

    

B.     

    

C.     

    

D.    

    

E.     

    

Answer: D

    

GWD23-Q2:

    

The function f is defined for each
positive three-digit integer n by f(n) = 2^x 3^y
5^z, where x, y, and z are the
hundreds, tens, and units digits of n, respectively.  If m and v are three-digit
positive integers such that f(m) = 9 f(v), then m
- v =

    

 

    

A.    
8

    

B.     
9

    

C.     
18

    

D.    
20

    

E.     
80

    

Answer: D

    

GWD24-16

    

From May 1 to May
30 in the same year, the balance in a checking account increased. What was the
balance in the checking account on May 30?

    

(1)   If, during this period of time, the
increase in the balance in the checking account had been 12 percent, then the
balance in the account on May 30 would have been $504

    

(2)   During this period of time, the increase in
the balance in the checking account was 8 percent.

    

 

    

    

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

    

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

    

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

    

l       
EACH
statement ALONE is sufficient

    

l       
Statements
(1) and (2) TOGETHER are NOT sufficient

    

Answer: A

    

GWD23-Q34:

    

                                                  E

    

            

                
                        
                    
                    
                        
                        
                    
                
         

    

 

    

 

    

 

    

 

    

    

      
         B                         C

    

 

    

 

    

 

    

 

    

 

    

 

    

              A            D

    

 

    

 

    

In the figure, each side of square ABCD has
length 1, the length of line segment CE is 1, and the length of line segment BE
is equal to the length of line segment DE. 
What is the area of the triangular region BCE?

    

 

    

A.    
1/3

    

B.     
(Ö2)/4

    

C.     
1/2

    

D.    
(Ö2)/2

    

E.     
3/4

    

 

    

 

    

Answer: B

    

GWD24-20

    

Of the 32 students
in a certain class, 15 are in a music club and 20 are in a dance club. If 10 of
the students are not in either club, how many of the students are in only one
of the two clubs?

    

A. 5   B. 9  
C.10   D. 17   E. 25  

    

Answer: B