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
0 = (9-9)/16
2 = 1+(sqrt 9+sqrt 9)/6, 1/9*sqrt 9*6
etc.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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