1.
5002-802=243600.
2.a)
;; 1995 is deficient;

b)
1997 is a prime number. 1997 is deficient;
c)
1999 is a prime number. 1999 is deficient.

3.
4.
P(A)=4/36=1/9, P(B)=20/36=5/9, P(A|B)=2/20=1/10, , P(A|C)=4/27 and P(B|C)=15/27=5/9.

5-6.a)
b)
c)
65 and 25;
d)
e)

7.a)
18!;
b)
18C3.
8.a)
mean =5, the average deviation=40/7 and the standard deviation
b)
five-number:-5,-2,7,10,13;

9.a)
;(-1,2,5,0) is outside of the hypersphere;

b)
;(1,9,9,7) is inside of the hypersphere;

c)
;(1,9,9,8) is inside of the hypersphere;

10.
;the equation is (x-1)2+(y-9)2+(z-9)2+(t-8)2=162;

11.
; Thus the maximum possible distance is and the minimum possible distance is .

Jie Wu
12/8/1997