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K-12 Math Puzzles || Ruth Carver's Home Page
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Challenge: Using the digits in 1997 and any operations, try to write equations that have the numbers from 0 to 100 as the answer.

Winning the Spot: The answer for each number and the name of the first person to get it will be posted.

Example: For 1996, some possible equations were

The numbers need not be in order but in case of a tie, the person who got the answer without rearranging the digits or by using the least number of operations will win the spot.

Alternate Solutions and their authors will also be posted for answers with the digits in order and the least number of operations used.

Thanks to my friend and colleague, Dick Davies of Germantown Academy, for sharing this activity with me.

Submit An Answer:: If you think you have an equation that equals any of the numbers not yet answered, Send It In!

Answer      Equation                Submitted by         
0  (9-9)/17
  1*(9-9)*7
  Ang Ngee Hiong, Singapore
  Brent Tworetzsky
1  9+9-17
  1^997
  1*9-gamma(9)/7!
  Ang Ngee Hiong, Singapore
  Brent Tworetzsky
  Greg Wong, Germantown Academy, PA
2  (9+7)/(9-1)
 sqrt((19+9)/7)
  Ang Ngee Hiong, Singapore
 Denis Denisenko, Moscow Russia
3  19-9-7
  1^9+9-7
  log(1+9)+9-7
 sqrt (1+99)-7
 (1/.9)(9)-7
  Ang Ngee Hiong, Singapore
  Brent Tworetzsky
  Greg Wong, Germantown Academy, PA
 Brent Tworetzsky
 Trevor Gile, BHS, Clovis, CA
4  (19+9)/7  Ang Ngee Hiong, Singapore
5  (9-7)*sqrt 9 -1
  -1 -9/9+7
 1*sqrt 9+9-7
  Ang Ngee Hiong, Singapore
  Greg Wong, Germantown Academy, PA
 Paul Mantegna, Upper Twp M.S., NJ
6  9-9+7-1
  -1*9/9+7
  Ang Ngee Hiong, Singapore
  Greg Wong, Germantown Academy, PA
7  (9*1)-9+7
  1*9-9+7
  Ang Ngee Hiong, Singapore
  Greg Wong, Germantown Academy, PA
8  9-9+7+1
  1+9-9+7 & 1^99+7
  Ang Ngee Hiong, Singapore
  Jon Harris, Upper Twp M.S., NJ
9  (9-7+1)*sqrt 9
  1+9/9+7
  Ang Ngee Hiong, Singapore
  Brent Tworetzsky
10  9-7-1+9
  -1+9+9-7
 1*9/sqrt 9+7
  Ang Ngee Hiong, Singapore
  Nicole Scrofani, Upper Twp. M.S., NJ
 Brent Tworetzsky
11  7*sqrt 9 -9-1
  19-gamma(9)/7!
  log(1+9)+sqrt 9+7
  (1*9)+9-7
  Ang Ngee Hiong, Singapore
  Greg Wong, Germantown Academy, PA
  Greg Wong, Germantown Academy, PA
  Erin Tracey, Upper Twp M.S., NJ
12  9-7+9+1
  1+9+9-7
  Ang Ngee Hiong, Singapore
  Greg Wong, Germantown Academy, PA
13  7*sqrt 9 -9+1
  log(1)+sqrt 9+sqrt 9+7
  Ang Ngee Hiong, Singapore
  Greg Wong, Germantown Academy, PA
14  9-sqrt 9+7+1
  1+sqrt 9+sqrt 9+7
  Ang Ngee Hiong, Singapore
  Greg Wong, Germantown Academy, PA
15  sqrt 9*sqrt 9+7-1
  -1^9+9+7
  -1+sqrt (9*9)+7
  Ang Ngee Hiong, Singapore
  Brent Tworetzsky
  Erin McIntyre, Upper Twp M.S., NJ
16  sqrt 9*sqrt 9+(7*1)
 -(1-9)(9-7)
  Ang Ngee Hiong, Singapore
 Denis Denisenko, Moscow Russia
17  19-9+7
  1^9+9+7
 sqrt(1+99)+7
 (1/.9)(9)+7
  Ang Ngee Hiong, Singapore
  Brent Tworetzsky
 Brent Tworetzsky
 Trevor Gile, BHS, Clovis, CA
18  (1*9)(9-7)  Kelly Brown, Upper Twp, NJ
19  9*sqrt 9-7-1
  1+9(9-7)
  Ang Ngee Hiong, Singapore
  Brent Tworetzsky
20  9*sqrt 9-(7*1)
  (1+9)(9-7)
  1+9+sqrt 9+7
  Ang Ngee Hiong, Singapore
  Brent Tworetzsky
  Kathy Schuler, Upper Twp., NJ
21  1+9*sqrt 9-7
  19+9-7
  19+9-7
 1^9*sqrt 9*7
  Ang Ngee Hiong, Singapore
  Greg Wong, Germantown Academy, PA
  Brent Tworetzsky
 Kevin Trotter, Escuela Americana, San Salvador
22 1^9+sqrt 9*7  Kevin Trotter, Escuela Americana, San Salvador
23  19-sqrt 9+7  Ang Ngee Hiong, Singapore
24  9-1+9+7
  -1+9+9+7
  Ang Ngee Hiong, Singapore
  Ryan Surace, Upper Twp M.S., NJ
25  (9*1)+9+7
  (1*9)+9+7
  Ang Ngee Hiong, Singapore
  Jon Harris, Upper Twp M.S., NJ
26  1+9+9+7  Ang Ngee Hiong, Singapore
27  9*(9-7+1)
 sqrt(sqrt(1/9*9^7))
  Ang Ngee Hiong, Singapore
 Denis Denisenko, Moscow Russia
28 99-71
 (1+sqrt(sqrt(9*9)))*7
 Joey Galante, Upper Twp M.S., NJ
 Denis Denisenko
29  7*sqrt 9+(9-1)
 -1+9+sqrt 9*7
  Ang Ngee Hiong, Singapore
 Taija Young, Upper Twp M.S., NJ
30  7*sqrt 9 +(9*1)
 1*sqrt 9*(sqrt 9+7)
  Ang Ngee Hiong, Singapore
 Denis Denisenko, Moscow Russia
31  7*sqrt 9+(9+1)
 (1+(sqrt 9)!^sqrt 9)/7
  Ang Ngee Hiong, Singapore
 Denis Denisenko, Moscow Russia
32 (-1+9) * ((-sqrt9) +7) Dave Krasik
33 -1+sqrt 9*9+7 Kevin Trotter, Escuela AMericana, San Salvador
34 1*sqrt 9*9+7
 1*sqrt 9*9+7
 Matt Palombo, Upper Twp M.S., NJ
 Kevin Trotter, Escuela AMericana, San Salvador
35  17+9+9
  19+9+7
 1+sqrt 9*9+7
  Ang Ngee Hiong, Singapore
  Gene Hall
 Kevin Trotter, Escuela AMericana, San Salvador
36 (1*9)*(-sqrt 9+7) Mark Stainthorpe, Upper Twp M.S.,NJ
37 ((sqrt 9+1)*7)+9
 (1+9)sqrt 9+7
 Derek Sorum
 Denis Denisenko, Moscow Russia
38 19(9-7) Andrea Smith, Upper Twp M.S., NJ
39 -1(sqrt9)+[(sqrt9)!*7] Dave Krasik
40 (1+9)*sqrt(9+7) Robin Damion
41 -1+(9-sqrt 9)*7 Jeremy Latimer, Upper Twp M.S., NJ
42 1*(9-sqrt 9)*7 Jeremy Latimer, Upper Twp M.S., NJ
43 1+(9-sqrt 9)*7
 (1+sqrt 9)*9+7
 Jeremy Latimer, Upper Twp M.S., NJ
 Kevin Trotter, Escuela American, San Salvador
44  -19+(9*7)  Brent Tworetzsky
45 (7-1)*9-9
 (1+sqrt 9)!+sqrt 9*7
 Antonella Catalioti, Upper Twp M.S., NJ
 Denis Denisenko, Moscow Russia
46 1+(sqrt9)+[(sqrt9)!*7] Dave Krasik
47 -1+[sqrt9*(9+7)] Dave Krasik
48 1[sqrt9*(9+7)] Dave Krasik
49 (1+sqrt 9+sqrt 9)*7 Lauren Robertson
50 (19 * sqrt9) - 7 Dave Krasik
51 1(9)+[(sqrt9)!*7] Dave Krasik
52 (7/.1)-9-9
 (-1+(sqrt 9)!)*9+7
 Trevor Gile, BHS, Clovis, CA
 Denis Denisenko, Moscow Russia
53  -1-9+(9*7)  Brent Tworetzsky
54  (7-1)*sqrt 9*sqrt 9
 -(1*9)+(9*7)
 -1*9+9*7
  Ang Ngee Hiong, Singapore
 Brent Tworetzsky
 Denis Denisenko, Moscow Russia
55 1-9+(9*7) Brent Tworetzsky
56 [(1+(sqrt9)!)*9]-7 Dave Krasik
57 (-1+(sqrt 9)!)!-9*7 Denis Denisenko, Moscow Russia
58 [1-(sqrt9)!] + (9*7) Dave Krasik
59 -1+[(sqrt9)!]*[(sqrt9)+7] Dave Krasik
60 79-19
 -1+9*(sqrt 9)!+7
 William Davenport, Kittredge Magnet School, Atlanta, GA
 Denis Denisenko, Moscow Russia
61 (7/.1)-(sqrt 9)!+sqrt 9
 1-sqrt 9+9*7
 Trevor Gile, BHS, Clovis, CA
 Denis Denisenko, Moscow Russia
62 -1+sqrt 9*sqrt 9*7
 -1^9+(9*7)
 Kevin Trotter, Escuela American, San Salvador
 Brent Tworetzsky
63  (7/1)*sqrt 9*sqrt 9
  (1^9)(9*7)
 1*sqrt 9*sqrt 9*7
  Ang Ngee Hiong, Singapore
  Brent Tworetzsky
 Kevin Trotter, Escuela American, San Salvador
64 1^9+(9*7) Brent Tworetzsky
65  7(9-1)+9
 -1+sqrt 9+9*7
  Erik Hall
 Denis Denisenko, Moscow Russia
66 1(sqrt9)+(9*7) Dave Krasik
67 (7/.1)-(sqrt 9)!-sqrt 9
 1+sqrt 9+9*7
 Trevor Gile, BHS, Clovis, CA
 Denis Denisenko, Moscow Russia
68 [-1+(sqrt9)!]+(9*7) Dave Krasik
69 (7/.1)-(9/9)
 -sqrt(1*9)+9!/7!
 Trevor Gile, BHS, Clovis, CA
 Denis Denisenko, Moscow Russia
70  (19-9)*7  Greg Wong, Germantown Academy, PA
71 -1+9+(9*7) Brent Tworetzsky
72  (7+1)*sqrt 9*sqrt 9
 1*9+9*7
  Ang Ngee Hiong, Singapore
 Dana Rogan, Upper Twp M.S.,NJ
73  (9*9)-7-1
  1+9+(9*7)
 -1+9*9-7
  Ang Ngee Hiong, Singapore
  Brent Tworetzsky
 ShawnMcHelvey, Upper Twp M.S.,NJ
74  (9*9)-(7*1)
  (1*9*9)-7
  Ang Ngee Hiong, Singapore
  Brent Tworetzsky
75  (9*9)-7+1
  1+(9*9)-7
  Ang Ngee Hiong, Singapore
  Brent Tworetzsky
76 (7/.1)+sqrt 9+sqrt 9
-19(sqrt 9-7)
 Trevor Gile, BHS, Clovis, CA
 Denis Denisenko, Moscow Russia
77 -1+[(sqrt9)!]*[(sqrt9)!+7] Dave Krasik
78  -19+97  Greg Wong, Germantown Academy, PA
79 (7/.1)+(sqrt 9)!+sqrt 9
 -1+9*9-int(sqrt(sqrt 7))
 Trevor Gile, BHS, Clovis, CA
 Kevin Trotter, San Salvador
80 1^9*gamma(7)/9 &
 1*9*9-int(sqrt(sqrt 7))
 Kevin Trotter, Escuela Americana, San Salvador
81  91-sqrt 9-7
 -1+9*9+int(sqrt(sqrt 7))
 1*9^(9-7)
  Ang Ngee Hiong, Singapore
 Kevin Trotter, San Salvador
 Denis Denisenko, Moscow Russia
82  19+(9*7)  Brent Tworetzsky
83  (1+9)(9)-7
 1*9*9+int(sqrt 7)
  Brent Tworetzsky
 Kevin Trotter, San Salvador
84 (1+sqrt 9)*sqrt 9*7
 1+9*9+int(sqrt 7)
 Erik Mateer, Upper Tw M.S, NJ
 Kevin Trotter, San Salvador
85 1+[((sqrt9)+9)*7] Dave Krasik
86 (9/.1)-7+sqrt 9
 -1+(sqrt 9)!!/9+7
 Trevor Gile, BHS, Clovis, CA
 Denis Denisenko, Moscow Russia
87  97-1-9
  -1-9+97
 -1+9*9+7
  Ang Ngee Hiong, Singapore
  Greg Wong, Germantown Academy, PA
 Dana Rogan, Upper Twp M.S.,NJ
88  97-(9*1)
  (1*9*9)+7
  Ang Ngee Hiong, Singapore
  Brent Tworetzsky
89  97-9+1
  1+9*9+7
  Ang Ngee Hiong, Singapore
  Greg Wong, Germantown Academy, PA
90 97-(sqrt 9)!-1
 1*9*(sqrt 9+7)
 Trevor Gile, BHS, Clovis, CA
 Kevin Trotter, San Salvador
91  19+9!/7!
  -1+99-7
  Greg Wong, Germantown Academy, PA
  Brent Tworetzsky
92  (99-7)/1
  (1*99)-7
  Ang Ngee Hiong, Singapore
  Brent Tworetzsky
93  1+99-7  Brent Tworetzsky
94 (9/.1)+7- sqrt 9
 1*((-(sqrt 9))+97
 Trevor Gile, BHS, Clovis, CA
 Kevin Trotter, San Salvador
95 1+(-(sqrt 9))+97 Kevin Trotter, San Salvador
96 -1^9+97 Kevin Trotter, San Salvador
97  (1+9)(9)+7
 1mod 9*97
  Brent Tworetzsky
 Kevin Trotter, San Salvador
98  (1^9)+97  Brent Tworetzsky
99 97+sqrt 9-1
 -1+sqrt 9+97
 Trevor Gile, BHS, Clovis, CA
 Denis Denisenko, Moscow Russia
100  log(1)+sqrt 9+97  Greg Wong, Germantown Academy, PA

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