PCTM Online
The PCTM Puzzle of the Week - Solutions

Special Congratulations to Mr. Boito's 8th grade Algebra 1 class from Moshannon Valley Jr.Sr. H.S. who sent in an "almost" complete list.

Lists of answers can also be found at:
http://mathforum.org/midpow/1997.chart.html and http://dimacs.rutgers.edu/~hochberg/game1997/

5- 9+sqrt(9)-7*1
64-  (9!/7!)-9+1
55-  9*7-9+1

9+1+9+7= 26
7+1+9+9=26
(1+7)9+9=81
i hope this is what you were asking for

I have a couple answers for the 1997 problem.

9 = 9/9+7+1

24 = 9+9+7-1

25 = 7*1+9+9

53 = 9*7-9-1

71 = 9*7+9-1

72 = 9*7*1+9

73 = 9*7+9+1

74 = 9/1*9-7

87 = 9*9+7-1

89 = 9*9+7+1

1997 Puzzle (? means square root)
1 = 7 - (?9 + ?9) * 1
2 = (9 + 7) - (9 - 1)
3 = 9 / (9 - 7 + 1) 
4 = (9 - 1) / (9 - 7)
5 = 7 - (9 / 9) - 1
6 = 7 - (9 / 9) * 1
7 = 9 * 1 - 9 + 1
8 = 1 + 9 - 9 + 7
9 = 9 / 9 +7 + 1
10 = 9 - 7 + 9 - 1
11 = 9 - 7 + 9 * 1
12 = 1 + 9 + 9 - 7
13 = (9 + 7) - ?9 * 1
14 = (9 / 9 + 1) * 7
15 = (?9 * ?9) + 7 - 1
16 = (9 - 7)(9 - 1)
17 = (9 - 7) * 9 - 1
18 = (9 - 7) * 9 * 1
19 = (9 - 7) * 9 + 1
20 = (9 - 7)(9 + 1)
21 = ?9 * 9 - 7 + 1
22 = (?9 * 7) + 1^9
23 = [ (?9 * 7) + ?9 ] - 1
24 = (7 + 9) + (9 - 1)
25 = 1 * 9 + 9 + 7
26 = 1 + 9 + 9 + 7
27 = [ (9 - 7) + 1 ] * 9
28 = [ (9 / ?9) + 1 ] * 7
29 = ?9 * 7 + 9 - 1
30 = ?9 * 7 + 9 * 1
31 = ?9 * 7 + 9 + 1
32 = 
33 = (7 + ?9 + 1) * ?9
34 = ?9 * 9 + 7 * 1
35 = ?9 * 9 + 7 + 1
36 = (9 - ?9)(7 -1)
37 = ?9 * (9 + 1) + 7
38 = [ 7^(?9) - 1 ] / 9 
39 = (?9)! * (7 + 1) - 9 
40 = (?9 + 1) + 7 + 9
41 = (?9 + ?9) * 7 - 1
42 = [ 7 * (?9 + ?9) ] * 1
43 = (?9 + ?9) * 7 + 1
44 =
45 = (7 - 1) * 9 - 9
46 = 7[(?9)!] + ?9 + 1
47 = (9 + 7) * ?9 - 1
48 = (?9 + ?9)(7 + 1)
49 = 7 * (?9 + ?9 + 1)
50 = (?9)! * 7 + (9 - 1)
51 = [ 9 * (7 - 1) ] - ?9
52 = (?9)! * 7 + (9 + 1)
53 = (9 * 7) - (9 + 1) 
54 = (9 * 7) - (9 * 1)
55 = 1 + 7 * 9 - 9
56 = [ 7! / (9 + 1) ] / 9
57 = [ 9 * (7 - 1) ] + ?9
58 = 9 * 7 - [(?9)!] + 1
59 = 9 * 7 - ?9 - 1
60 = 9 * 7 - ?9 * 1
61 = (9 + 1) * 7 - 9
62 = ?9 * ?9 * 7 - 1
63 = (7 - 1) * 9 + 9
64 = ?9 * ?9 *7 -1
65 = (9-1)7 +9
66 = 9 * 7 + ?9 * 1
67 = 9 * 7 + ?9 +1
68 = 9 * 7 + (?9)! - 1
69 = 9 * 7 + (?9)! * 1
70 = (7! / 9) / (9 - 1)
71 = 9 * 7 + 9 - 1
72 = 9 * 7 + 9 * 1 
73 = 9 * 9 - 7 - 1
74 = 9 * 9 - 7 * 1
75 = 9 * 9 - (7 - 1)
76 = 
77 = 7 * (?9 + 9 - 1)
78 =
79 = (9 + 1) * 7 + 9
80 = (9 - 1) * (?9 + 7)
81 = 9 * (7 + 1) + 9
82 = 9^(9 - 7) + 1
83 = (9 + 1) * 9 - 7
84 = (?9 + 9) * 7 * 1
85 = (?9 + 9) * 7 + 1
86 = 
87 = 9 * 9 + 7 - 1
88 = 9 * 9 + 7 * 1
89 = 9 * 9 + 7 + 1
90 = 9(?9 + 7) * 1
91 = 7(?9 + 1 +9)
92 = 
93 = 
94 = 
95 = 
96 = (?9 + 9) * (7 + 1)
97 = (1 + 9) * 9 + 7
98 = 
99 = (7 + ?9 + 1) * 9
100 = (?9 + 7) * (9 + 1) 

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