E-mail: info@ahmath.com

AhMath Real than i, rational than π

Arf League

hide this To submit your answers you need to log in.
If you are not a member of this page and if your name is not listed in the score tables, you need to sign up first. Otherwise, please read the following instructions given below!

hide this This is the place where you can find the most valuable Mathematical Olympiads books!

New pages from AhMath: Unordered Times Table, Unordered Divisibility Test, Bulls and Cows Game, Unique Bid Auction Game, and Guess My Country. Check them out!

Explore all your possibilities. Udemy online courses on sale from $11.99
Bookmark and Share

A new problem will be released soon.

☆★☆★☆★  Newest Problem!  ★☆★☆★☆

132. Problem: A64C , proposed by Ahmet Arduc
132 is the smallest number which is the sum of all of the 2-digit numbers that can be formed with its digits. Challenging Math Problem: A64C

Format of the items of the selection menu: Problem Order, Problem Code (Difficulty Level). Red problems have a difficulty level of less than 0.75, thus, as an example, a 0.18 means only 18% of all answers submitted are correct.

Number of Responses: 5794
Number of Correct R.: 3993
Difficulty Level: 68.92
1. Problem: 595A , proposed by Ahmet Arduc, Tip: Key Fact(s): 7695
1 is the multiplicative identity.
Challenging Math Problem: 595A
Correct answers have been submitted by:
1. Mohamed Karamany
2. Jeffrey Robles
3. Joseph Rodelas
4. Mahmut Cemrek
5. Suleyman Akarsu
6. Yavuz Selim Koseoglu
7. John Gamal Aziz Attia
8. Serkan Callioglu
9. Βαρελάς Γεώρ𝛾ιος
10. Marvin Cato
11. Isaiah James de Dios Maling
12. Joselito Torculas
13. John Albert A. Reyes
14. Nheil Ignacio
15. Gerald M. Pascua
16. Angelu G. Leynes
17. Roenz Joshlee Timbol
18. Rindell Mabunga
19. Caed Mark Medul Mendoza
20. Russel J. Galanido
21. Melga Sonio
22. Mark Elis Espiridion
23. Adrian Pilotos Burgos
24. Sumet Ketsri
25. Daniel James Molina
26. Nixon Balandra
27. Jacob Sabido
28. Poetri Sonya Tarabunga
29. John Patrick
30. Lilanie Monique Torilla
31. Chris Norman Algo
32. Christian Daang
33. Grant Lewis Bulaong
34. Richard Phillip Dimaala Fernandez
35. Jake Gacuan
36. Ibrahim Demir
37. Christian Paul C. Patawaran
38. Amirul Faiz Abdul Muthalib
39. Norwyn Nicholson Kah
40. Jhepoy Dizon
41. Ralph Macarasig
42. Dan Lang
43. Chayapol
44. Dreimuru Tempest
45. Kurara Chibana
46. Lim Jing Ren
47. Alea Astrea
48. Kumar Ayush
49. Joem Canciller
50. Gluttony
51. Serdal Aslantas
52. Radu Bogo
53. Barry Villanueva
54. Randy Orton
55. Captain Magneto
56. Willie Revillame Wowowin
57. Mertkan Simsek
58. Mark Lawrence P Velasco
59. Srinivas Kanigiri
60. Prince Ivan Paraiso
61. Dale Angelo Azas Cortez
62. Mythreya Lakshman
63. Bikram Chohan
64. Law Tik Shun
65. Gideon Tomas
66. Jereco Dela Pena
67. John Aries Sarza
68. John Kenneth Vito Cruz
69. echo gabata
70. Anjelo V. Racho
71. Darwin Ojera
72. Andrei Alido
73. Sam Kashkooli
74. Mark Kenneth Dairo
75. Adisa Tolani
76. Hanelet Santos
77. Reygan Medina Dionisio
78. Angelo Velasquez
79. Marvin Cato
80. Jade N. Mijares
81. Kot Behemot
82. Lee Csek
83. Charles Dwight M. Pelaez
84. Fujiwara Toneri
85. Arcy Leann
86. Daryll Ko
87. Mark David Mortel Dela Cruz
88. Maureen Jordan
89. Zhuo Qun Song
90. Rik Smoody
91. Max Wong
92. Hanz U. Baga
93. Angelo M. Velasquez
94. angelo magdaong
95. Vaibhav Priyadarshi
96. Romeo Dane D. Melendrez
97. Bryant Ularte
98. Lisa Sauermann
99. Sajib Kumar Chowdhury
100. Raffy Salazar
101. Christian Rozano
102. Lourenz Miguel Paras
103. Ric Tura Jr
104. charles edward
105. Angelo Bungcaras Magdaong
106. Ramon Villota
107. Ian Galang
108. Joem Canciller

Futured Math Enthusiasts

The first problem
is solved firstly by
Mohamed Karamany
Last solved problem
by Joem Canciller
Coming Soon
Long Jumper
Coming Soon
Marathon Runner
Number of page views
since 11.11.2019

Score Table - Math Enthusiasts (only the first 100)

Score depends on number of correct answers and number of trials.

  • FS stands for First Solver. For each problem, there is a first solver. Each time you solve a problem as the first person your FS score increases by one.
  • SF stands for Solution Files. Some of the Math Enthusiasts sends solutions to the problems. This is to promote their valuable contribution to the Arf League.
  • SP stands for Sniper. You can get this badge if and only if you do not miss any problem in your first try and solve them correctly. Only snipers have the potential to get the full score.
  • UT stands for User Type. "MT" is for Math Teacher and "S" is for Student.

hide this Please submit your country to be listed in this table!

Joem Canciller
charles edward
Jay Lee
Romeo Dane D. Melendrez
Order Score # of Correct Answers Names Badges Country
1.097.73130Angelo M. Velasquez13047S PhilippinesPhilippines
2.083.69127Lee Csek1272 ChinaChina
3.083.63117Lisa Sauermann1172S GermanyGermany
4.083.05123Zhuo Qun Song1232S CanadaCanada
5.076.71122Daryll Ko1220S PhilippinesPhilippines
6.076.48115Isaiah James de Dios Maling11534MT PhilippinesPhilippines
7.075.22128Caed Mark Medul Mendoza128112MT PhilippinesPhilippines
8.060.3194Jeffrey Robles945 PhilippinesPhilippines
9.056.20103Reygan Medina Dionisio1032MT PhilippinesPhilippines
10.052.1392Richard Phillip Dimaala Fernandez9290MT PhilippinesPhilippines
11.050.7667Lilanie Monique Torilla6755S PhilippinesPhilippines
12.049.9684Jereco Dela Pena840MT PhilippinesPhilippines
13.047.7765Sumet Ketsri6567 ThailandThailand
14.045.4671Amirul Faiz Abdul Muthalib710MT MalaysiaMalaysia
15.042.4369Radu Bogo6945 RomaniaRomania
16.041.0262Kurara Chibana620S JapanJapan
17.040.9154Willie Revillame Wowowin540 PhilippinesPhilippines
18.040.6363Russel J. Galanido6330S South KoreaSouth Korea
19.035.8766Mertkan Simsek660MT TurkeyTurkey
20.035.8279Christian Paul C. Patawaran791S PhilippinesPhilippines
21.035.0654Marvin Cato5130MT PhilippinesPhilippines
22.031.7366Fujiwara Toneri666S JapanJapan
23.031.3162Arcy Leann6215S PhilippinesPhilippines
24.030.5752Law Tik Shun520MT Hong KongHong Kong
25.028.6148Nixon Balandra4846MT PhilippinesPhilippines
26.028.3254Randy Orton540 United States of AmericaUnited States of America
27.028.1260Rindell Mabunga6031S PhilippinesPhilippines
28.027.1549Raffy Salazar490S PhilippinesPhilippines
29.026.5235Arjun Singh Rajawat354S IndiaIndia
30.025.5745Rik Smoody450MT United States of AmericaUnited States of America
31.025.4741Jacob Sabido415S PhilippinesPhilippines
32.022.7441Darwin Ojera4122MT PhilippinesPhilippines
33.020.8841Joselito Torculas4126 PhilippinesPhilippines
34.020.1857Roenz Joshlee Timbol571S PhilippinesPhilippines
35.020.0436Lim Jing Ren360S MalaysiaMalaysia
36.019.7026Alea Astrea260S PhilippinesPhilippines
37.019.4830echo gabata300 VietnamVietnam
38.019.2536Lourenz Miguel Paras360S PhilippinesPhilippines
39.017.4441Hanz U. Baga4173S PhilippinesPhilippines
40.017.0726Kuba Helsztynski260MT PolandPoland
41.015.0626Sajib Kumar Chowdhury 260S BangladeshBangladesh
42.014.3919Lenard Guillermo192S PhilippinesPhilippines
43.013.7720Gluttony200 PhilippinesPhilippines
44.013.6430Angelo Bungcaras Magdaong301MT PhilippinesPhilippines
45.013.2729Joseph Rodelas290S PhilippinesPhilippines
46.012.6320Mark Alvero200MT PhilippinesPhilippines
47.012.4926Norwyn Nicholson Kah2638S PhilippinesPhilippines
48.012.4625Jhepoy Dizon250S PhilippinesPhilippines
49.012.4319Ramon Villota190S PhilippinesPhilippines
50.011.7532Daniel James Molina321S PhilippinesPhilippines
51.011.2220Ralph Macarasig200S PhilippinesPhilippines
52.011.1618Ric Tura Jr1821S PhilippinesPhilippines
53.010.6718Maureen Jordan181 SingaporeSingapore
54.010.6114John Albert A. Reyes146S PhilippinesPhilippines
55.009.9517Nheil Ignacio178S PhilippinesPhilippines
56.009.6522Hanelet Santos2215S PhilippinesPhilippines
57.009.5423Kumar Ayush231S IndiaIndia
58.009.1428Mark Kenneth Dairo2826S PhilippinesPhilippines
59.009.1217Ibrahim Demir171MT TurkeyTurkey
60.008.7718Francis Gerard Magtibay180S PhilippinesPhilippines
61.008.6620Charles Dwight M. Pelaez208S PhilippinesPhilippines
62.008.5519Bikram Chohan195S IndiaIndia
63.008.3311Melga Sonio110S PhilippinesPhilippines
64.008.2919angelo magdaong190MT PhilippinesPhilippines
65.008.0013Poetri Sonya Tarabunga130S IndonesiaIndonesia
66.007.4214Ewen Goisot1417 FranceFrance
67.007.0511Max Wong110S Hong KongHong Kong
68.007.0043Kimi No Nawa43166S JapanJapan
69.006.9621Christian Daang2125S PhilippinesPhilippines
70.006.7514Angelu G. Leynes140S PhilippinesPhilippines
71.006.5511Mark Elis Espiridion110 PhilippinesPhilippines
72.006.2617Stefano Ongari170S ItalyItaly
73.005.8213Chris Norman Algo1310S PhilippinesPhilippines
74.005.307Adrian Pilotos Burgos70 PhilippinesPhilippines
75.004.556Yavuz Selim Koseoglu60S TurkeyTurkey
76.004.556Mahmut Cemrek60 TurkeyTurkey
77.004.556John Gamal Aziz Attia61S EgyptEgypt
78.004.556Jade N. Mijares60S PhilippinesPhilippines
79.003.6613Aljun Emperado133S PhilippinesPhilippines
80.003.2527Keedgwh270 IndiaIndia
81.003.036Liu Chen60 ChinaChina
82.003.036Kevin Durant60S TurkeyTurkey
83.003.036John Lester Tan60S PhilippinesPhilippines
84.003.034Vaibhav Priyadarshi40S IndiaIndia
85.003.034Βαρελάς Γεώρ𝛾ιος40 GreeceGreece
86.002.715Kot Behemot50MT United States of AmericaUnited States of America
87.002.424Saket Singh Rajawat41S IndiaIndia
88.002.424Bryant Ularte40MT PhilippinesPhilippines
89.002.273Jomari Mama30MT PhilippinesPhilippines
90.002.273Gerald M. Pascua30 PhilippinesPhilippines
91.001.895Leandro Dar Juan50S PhilippinesPhilippines
92.001.895Ian Galang50S PhilippinesPhilippines
93.001.734Smahi Abdeslem44S AlgeriaAlgeria
94.001.734Elijah Evangelista40S PalauPalau
95.001.526David Paul 60S PhilippinesPhilippines
96.001.524Luke Robitaille 31S United States of AmericaUnited States of America
97.001.522James Harden20S PhilippinesPhilippines
98.001.363John Kenneth Vito Cruz30S PhilippinesPhilippines
99.001.104Mark David Mortel Dela Cruz40S PhilippinesPhilippines
100.001.012Isaiah John H. Leobrera20S PhilippinesPhilippines

hide this All problems are solved 3640 times.

Score Table - Countries

NOTE: Countries are listed according to their first answer submit dates.

Country # of Correct Answers # of Trials Performance
South KoreaSouth Korea637485.14%
United States of AmericaUnited States of America11716770.06%
Hong KongHong Kong648278.05%
  • Worked Solutions to the Problems
    Solutions to all Challenging Math Problems are ready!
    Solutions for the first 10 Challenging Math Problems
    If you want to get the pdf of all the questions with solutions please do the payment by using the paypal button given on the left.

    For more documents and info about olympiads, please click Olympiads.

  • Online Problem Solver

Key Facts

  • 1. Key Fact 7446 |Tags: product, rational, number, irrational
  • 2. Key Fact 7695 |Tags: fraction, lowest term, numerator, denominator, relatively prime
  • 3. Key Fact ABAD |Tags: square, even, integer, divisibility
  • 4. Key Fact BAB3 |Tags: square, odd, integer, divisibility
  • 5. Key Fact 988C |Tags: product, perfect square, consecutive numbers
  • 6. Key Fact 9A34 |Tags: divisibility
  • 7. Key Fact B664 |Tags: identity, factorial
  • 8. Key Fact 969B |Tags: identity
  • 9. Key Fact CE81 |Tags: identity
  • 10. Key Fact B945 |Tags: identity
  • 11. Key Fact BCC8 |Tags: factorial, inequality
  • 12. Key Fact 965A |Tags: identity
  • 13. Key Fact E856 |Tags: identity
  • 14. Key Fact 7C45 |Tags: Sophie-Germain, identity
  • 15. Key Fact EA1C |Tags: identity
  • 16. Key Fact 3E17 |Tags: identity, factorization
  • 17. Key Fact 2545 |Tags: identity, factorization
  • 18. Key Fact A376 |Tags: identity
  • 19. Key Fact 3278 |Tags: composite number
  • 20. Key Fact 2DCC |Tags: prime number, definition
  • 21. Key Fact 87D4 |Tags: prime number, composite number, 1
  • 22. Key Fact 9E11 |Tags: prime number, composite number, 1
  • 23. Key Fact A478 |Tags: prime number, even
  • 24. Key Fact 2AB2 |Tags: prime number
  • 25. Key Fact DAEA |Tags: prime numbers
  • 26. Key Fact 9ECE |Tags: prime factorization
  • 27. Key Fact 525C |Tags: prime number, composite number
  • 28. Key Fact 163E |Tags: Wilson's Theorem
  • 29. Key Fact 5221 |Tags: Bertrand's Postulate, prime number
  • 30. Key Fact 24D6 |Tags: Bonse's Inequality, prime numbers
  • 31. Key Fact C181 |Tags: prime, divisor
  • 32. Key Fact 8A33 |Tags: divisibility, square, odd, integer
  • 33. Key Fact 7B55 |Tags: divisibility
  • 34. Key Fact 8C41 |Tags: divisibility
  • 35. Key Fact 8632 |Tags: product, consecutive, integer, divisibility
  • 36. Key Fact EADA |Tags: divisibility
  • 37. Key Fact A4A7 |Tags: binomial expansion
  • 38. Key Fact 3845 |Tags: binomial expansion, number of terms
  • 39. Key Fact D8CD |Tags: identity
  • 40. Key Fact DEA5 |Tags: identity
  • 41. Key Fact 7B38 |Tags: identity
  • 42. Key Fact 2EBB |Tags: identity
  • 43. Key Fact 89DD |Tags: identity
  • 44. Key Fact ECD9 |Tags: chessboard, square
  • 45. Key Fact A86B |Tags: arithmetic mean, real numbers
  • 46. Key Fact B65C |Tags: geometric mean, real numbers
  • 47. Key Fact D477 |Tags: arithmetic mean, geometric mean, inequality
  • 48. Key Fact DDC5 |Tags: harmonic mean, real numbers
  • 49. Key Fact 29D9 |Tags: arithmetic mean, harmonic mean, inequality
  • 50. Key Fact 5375 |Tags: inequality
  • 51. Key Fact 1E7C |Tags: inequality
  • 52. Key Fact 3981 |Tags: inequality
  • 53. Key Fact 1EB9 |Tags: inequality, identity
  • 54. Key Fact D7B8 |Tags: inequality
  • 55. Key Fact 2483 |Tags: inequality
  • 56. Key Fact 6C13 |Tags: inequality
  • 57. Key Fact 7185 |Tags: inequality
  • 58. Key Fact 8C62 |Tags: inequality
  • 59. Key Fact 913D |Tags: inequality, identity
  • 60. Key Fact ADBA |Tags: Cauchy–Schwarz, inequality
  • 61. Key Fact 2169 |Tags: Chebyshev, inequality
  • 62. Key Fact E1B9 |Tags: line, intersection, parabola, abscissa, vertex, midpoint, line segment
  • 63. Key Fact 72A4 |Tags: De Moivre, formula
  • 64. Key Fact 5DB3 |Tags: fibonacci, numbers
  • 65. Key Fact 47EB |Tags: finite serie, finite sequence
  • 66. Key Fact 13D3 |Tags: infinite serie, infinite sequence
  • 67. Key Fact EAA4 |Tags: partial sum, series
  • 68. Key Fact 3332 |Tags: sequence, partial sum, series, limit
  • 69. Key Fact 2B69 |Tags: sequence, partial sum, series, limit
  • 70. Key Fact C62B |Tags: series, sum
  • 71. Key Fact 1529 |Tags: sum, infinite serie
  • 72. Key Fact E6E7 |Tags: relative error, measurement
  • 73. Key Fact 8B56 |Tags: angle, bisector, triangle
  • 74. Key Fact B4C3 |Tags: sum, exterior angles, convex, polygon
  • 75. Key Fact C4CC |Tags: triangle, circle, greatest area, isosceles triangle
  • 76. Key Fact 8146 |Tags: circle, plane, common tangent
  • 77. Key Fact B13A |Tags: lattice points, gcd, greatest common divisor
  • 78. Key Fact 4BC8 |Tags: right triangle, median
  • 79. Key Fact 2B31 |Tags: minimal polynomial
  • 80. Key Fact C77E |Tags: british flag theorem, rectangle, geometry
  • 81. Key Fact B9E9 |Tags: pythagorean triple, triangle
  • 82. Key Fact 865E |Tags: primitive pythagorean triples, triangle

If you want to be a problem (or key fact) writer, please contact AhMath by sending an email to challenging-problems@ahmath.com.

Ahmet Arduc, Mathematics Teacher

Ahmet Arduc

Question Writer

Number of questions: 113

Ahmet worked as a maths olympiad instructor for many years. He is the editor and co-author of the unpublished 484-page book “Mathematical Olympiad Preliminary Question Bank, with 1001 solved questions”. His students got high achievements in many local and national mathematical competitions.

Amirul Faiz Abdul Muthalib

Amirul Faiz Abdul Muthalib

Problem Writer

Number of problems: 10

With over 5 years of hands-on, successful teaching experience, Amirul is an enthusiastic Pre-University Mathematics Lecturer in INTEC Education College, Malaysia. Being a versatile individual who love Maths, he has earned a Master’s Degree in Mechanical Engineering in Japan. He had opportunity to teach Maths in Japanese Syllabus for scholarship sponsored students who will further their study in KOSEN (National College of Technology in Japan). He also train some of his students for the National Olympiad every year.

İhsan Yücel

İhsan Yücel

Problem Writer

Number of problems: 3

Ihsan is currently in the thesis phase of his postgraduate education, which is about mathematics teaching education. He got some notable national and international achievements in various secondary school mathematics and project competitions. He’s an author of many scientific articles about mathematics in the quarterly magazine "Mathematical World". He’s the founder of Matematik Meraklısı, a website dedicated to Mathematics.

Richard Phillip Dimaala Fernandez

Richard Phillip Dimaala Fernandez

Problem Writer

Number of problems: 1

Richard is an experienced math teacher in a Chinese school in the Philippines. He is a product of Philippine Normal University (National Center for Teacher Excellence). He trains students who compete in both local and international math competitions. He is a trainer in Mathematics Trainers' Guild, Philippines (MTG Philippines) and Metrobank-MTAP-DepEd Math Challenge (MMC). He is also a lecturer in one of the review centers specialized in university entrance examinations. He is also a Suken Test Passer (Mathematics Certification Institute of Japan).

Leave a Comment!

Please use the form below to send your general comments about Arf League. All fields are required!


It's a good way to practice maths and also the site encourages you to submit your answer with an accompanying solution. Participants can not just simply guess the answer or predict what will be the answer based on the given, they need to know and understand the topic. Also this refrains participants to just simply ask the answer from other people. So the method was excellent and people will definitely learn many things about math.

- Rindell Mabunga / Philippines

I want to say my deepest gratitude in creating this website. The questions are not the typical type and not normally taught to non-mathematical major degrees. I really hope that you'll continue your mission and vision in creating this site, as this serves as a platform to enhance our mathematical skills. Hoping for the best good luck!!!

- Russel J. Galanido / South Korea

I see AhMath as the one encouraging self-paced learning or practice in solving math problems. It does not put me into any kind of pressure like requiring myself to be the first one to solve the problems correctly and giving answers with a limited time. Also, it gives me excitement for the next problems to solve as well as for the appearance of my name on the list of the people who submitted the correct solutions and answers for those math problems. Overall, it gives me confidence to be better in math.
Thank you for everything, AhMath.

- Marvin Cato / Philippines

I knew AhMath from a facebook group, "Math Enthusiasts Quiz Group", that I just joined a few weeks ago. Then I found that there are the "challenging math problems" here that refresh my Math skill.
I like many ideas on this website, the word "Math Enthusiasts" exactly describes what I'm and it makes me recall the feeling about Math when I was young, it was fun and exciting!
I like the motto "Real than i, rational than n", it's playing in my head and I'm still doubt about its meaning :-D
There is no time constraint for solving the problems so we can think about the solutions in the different ways. Sometimes the new solutions reveal the beauty of Math and that only happens when we have time to think about other solutions.
Thank you the creator and moderator of this website, especially Ahmet Arduc, who brings me back to the feeling of fun and exciting with his creative problems.

- Sumet Ketsri / Thailand

Ahmath is basically a great site. The problems are really challenging and mind boggling. I really like the way that the Math enthusiasts should show the solution as well for each problem. You need to learn on your own. This site greatly help me improve my Math skills and writing solutions as well. Thank you much Ahmath for an amazing job. More power and God bless. "Train HARD, win EASY. Train Easy, win HARD". Hoping you all the best out there. Just continue on your aim to help the students as well as the non-students to further enhance their math skills. God bless and More power AHMATH FTW!!!

- Isaiah James de Dios Maling / Philippines

I want to thank sir Ahmet Arduc for creating this wonderful site AhMath. The "Challenging Math Problems" are really challenging. Most of the problems are math problems that you can't normally encounter in school. You can solve the problems in different ways. You can find some beautiful patterns while solving these problems. The problems are addictive especially the problems created by sir Ahmet. It brings me back the way i feel when i was young, the excitement and having fun when solving math problems. I'm always excited to see my name on the list of people who solved the problem correctly! I can say that I am really a Math Enthusiast now and I improved a lot with my mathematical skills. I also like that there is no time limit in solving the problems. You can solve the problems when you are not busy or you are in the mood to solve. Thank you Ahmath, I hope you'll continue to improve this site and help us to be better. Hoping you all the best, God bless!

- Caed Mark Medul Mendoza / Philippines

I am not one of the most gifted math wizards from my country. Through AhMath, I am able to hone my skills and at least par with them, although I am still far from their prowess. Some simple questions are masked to seem difficult and all problems that I have solved felt satisfying knowing that I was able to use, display, and hone my skills.

- Fujiwara Toneri / Japan

This is a good website for math enthusiast who wants to challenge their math ability. Thanks for questions that push us to think differently and of course to learn new things.. More powers and God Bless.

- Reygan Dionisio / Philippines

Explore all your possibilities. Udemy online courses on sale from $11.99
100% automatically remove the background from any photo with remove.bg
Go to top of page