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AhMath Real than i, rational than π

Arf League

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If you were 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!

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A new problem will be published as soon as the latest problem gets at least 5 solvers. 3 more solvers are needed to release the new problem.

☆★☆★☆★  Newest Problem!  ★☆★☆★☆

107. Problem: D2D2 , proposed by Ahmet Arduc
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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: 24
Number of Correct R.: 13
Difficulty Level: 54.17
1. Problem: 9918 , proposed by Ahmet Arduc
Number 2019 is not a Catalan number.
Correct answers have been submitted by:
1. Caed Mark Mendoza
2. Jeffrey Robles
3. Evan Phillip Mendoza
4. Mark Alvero
5. John Lester Tan
6. Rafael Zamora
7. James Harden
8. Miguel
9. Ryan Magdayo Caduyac
10. Jay Cyril Mijares
11. Reygan Dionisio

Futured Math Enthusiasts

The first problem
is solved firstly by
Mohamed Karamany
Last solved problem
by Reygan Dionisio
Coming Soon
Long Jumper
Coming Soon
Marathon Runner
Number of page views

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!

Order Score # of Correct Answers Names Badges Country
Reygan Dionisio0MT PhilippinesPhilippines
Caed Mark Mendoza1MT PhilippinesPhilippines
1Ryan Magdayo Caduyac0S PhilippinesPhilippines
1Rafael Zamora0S PhilippinesPhilippines
1Jeffrey Robles0 PhilippinesPhilippines
1James Harden0S PhilippinesPhilippines
1Evan Phillip Mendoza0S PhilippinesPhilippines
1 Mark Alvero0MT PhilippinesPhilippines
1Miguel0S PhilippinesPhilippines
1John Lester Tan0S PhilippinesPhilippines
1Jay Cyril Mijares0 PhilippinesPhilippines

hide this All problems are solved 15 times.

Score Table - Countries

Country # of Correct Answers # of Trials Performance

Score Tables for the Previous 104 Problems

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 contractor (problem writer, key fact writer, etc.), please contact AhMath by sending an email to challenging-problems@ahmath.com.

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. Likewise, his students also got many elementary and secondary level mathematical olympics achievements. In the recent past, his students got the first and the second place in the TÜBİTAK National Secondary School Research Projects Contest. One of his students, a team member of the national math team, received a bronze medal in IMO. 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).

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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

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