Qn from 2010 SMO (Junior) Special Round

Someone posted the following question on the cbox:
A student divides an integer m by a positive integer n, where n<=100 and claims that m/n=0.167a1a2... show the student must be wrong.

My solution:

SMO 2010 (Open) Special Round

I could only do 4.5 questions and at least 6 people could do all 5. So I failed. I did qns 1,2,3 in 1.5 hours and qn 5 in 1 hour, and I worked on qn 4 for 2 hours.

SMO 2010 (Senior) Special Round

It was raining very heavily this morning so we were almost late. All the questions were trivial except for maybe question 5 which I don't know anyone who could solve it.

But I only managed to solve 3 questions because of my stupidity.

After the competition, the 6 of us (IMO participants) and our trainers/teachers went to West Coz restaurant for a lunch treat.

Lim Min's Gathering with QtPS (6A'06) friends

Mouth-watering agar agar prepared by Melissa and Angela.

Glutinous rice, tao suan and spaghetti prepared by my mother.

Cupcakes prepared by Julene, pies and egg tarts bought from Leong Sang Hong Kong Pastries at Tiong Bahru.

Roast chicken bought from NTUC Fairprice.

Fried rice prepared by my 1st auntie.

Yao Qing, Jane, Agnes, Julene, Mahadhir, Derek, Kai Jie, Wei Wu

Lim Li choosing food.

Miss Chai, Mr Ng, Joanne.

Jeremy Sim, Sultan, Jia He, Derek, Nicky.

Julene, Yao Qing, Jane, Bun Heng, Wei Wu, Daren, Yuni.

Yuni, Agnes, Melissa.

SIMO Camp Photos

Too lazy to blog. Some of the photos were taken from Ding Yue's facebook.

Back of SIMO t-shirt. It says 'SIMO' at the top - too bad if you don't understand.

First night activity - suicide chess. We also played cling and form/delete word game. Find Lim Min.

Eventually white won (not this group).

Everyone fails to find Yan Sheng's manliness in this game.

Grouping for vertical training. The IMO people are on top. Fail: Ivan. Tall One: Vincent. Cling: Lim Jeck. Flirt: Ang Yan Sheng. Ren Ping: Gabriel. Pikachu: Ang Jie Jun.

Aiyoh: Joseph Kuan. Li Li Potter: Lee You Jun. Chops: Zhan Xiong (maybe). Elmo: Tan Xin Xuan

Failed NUS High turnstile. Just randomly taking. Don't really know who got stuck.

Last dinner at NUS Bistro. Find me.

SMO 2010 (Junior) answers

Contributed by 'NAMELESS', 'hz' and some other random people (thank you!). I have done the remaining 8 or so questions.
1. E
2. D
3. B
4. C
5. A
6. D
7. E
8. B
9. C
10. C
11. 2010
12. 369
13. 51
14. 26
15. 16
16. 322
17. 1139
18. 4021
19. 200
20. 01
21. 2250
22. 31
23. 100
24. 2010
25. 177
26. 3350
27. 672
28. 144
29. 25
30. 11
31. 0
32. 23
33. 42
34. 31680
35. 60

Let me know if you have different answers and you believe you are right.

For the next 6 days (4 - 9 Jun), Lim Min and I will be at the SIMO camp, which is at NUS High.

SMO 2010 (Open) Answers

I think the following answers are correct, with inputs from NUS High and RI friends. Anyone knows of other answers please let me know.
1. 50
2. 199
3. 1159
4. 65
5. 78
6. 2500
7. 26
8. 8038
9. 45
10. 4
11. 11
12. 22023
13. 4021
14. 14
15. 3
16. 8030
17. 841
18. 18
19. 17
20. 10045
21. 2007
22. 12345
23. 86422
24. 309
25. 2011

SMO 2010 (Senior) Answers

My sister and I took the SMO(Senior) today. We checked our answers and with some inputs from NUS High and RI friends, I think these are the correct answers:
1. A
2. E
3. E
4. C
5. B
6. E
7. D
8. B
9. D
10. C
11. 132
12. 2575
13. 501
14. 35
15. 1994
16. 1005
17. 216
18. 27
19. 2010
20. 60
21. 2
22. 65
23. 72
24. 32
25. 2002
26. 49
27. 112
28. 60
29. 6
30. 680
31. 2780
32. 5
33. 360
34. 75
35. 12

Our New Toy

My father bought an iPad. It was shipped from US and we received it yesterday. I think it costs US$7xx (about S$1000). We downloaded many free games and utilities from the Internet (Apple iTunes Store).

Year 3 Semester 1 Results

My semestral GPA is 4.6 (max is 5). I did badly for Fine Art. I look forward to dropping this subject in 1.5 years' time. For Year 5 & 6, I would like to take Maths Major with Honours (already taking it now), Physics Major with Honours, Chemistry Major with Honours and Computer Science Major.

Singapore Team to 51st IMO

The results for the Singapore National Team for 51st International Mathematical Olympiad were released today. Out of the 6 participants selected, 2 are from RI-JC (Ivan Loh and Vincent Tseng), 1 from ACS(I) (Ang Jie Jun) and 3 from NUSH (Ang Yan Sheng, Gabriel Wong and I).

The 51st IMO will be held in Astana, the Republic of Kazakhstan. I do not know much about the country so I googled it - the Republic of Kazakhstan is in Eurasia and ranked as the ninth largest country in the world, and its location is below:


Training for the Singapore IMO national team will start next Thu (20/5) at NUS Maths Dept, and will stretch all the way to the competition itself, which is from 4 Jul to 15 Jul. Just like last year, my 1-month June holidays will be spent on training and I am going to miss many lessons again when school reopens ...

Art of Problem Solving

I think The Art of Problem Solving is the best resource for Maths problem solving. You can also train your quick thinking by playing Maths games with other people. Try FTW! to pit your Maths skills in solving AMC kind of questions against other Maths enthusiasts. At the end of a game, you will be rated against other registered players.

If you have any Maths problems, go to mathlinks.ro and post your problems there (instead of spamming my cbox :) ), and hopefully someone else will answer it for you. It has forums for primary school kind of Maths questions, to high school types, to Maths Olympiad questions, college/university Maths and even Arts and Sciences.
http://www.artofproblemsolving.com/Forum/index.php

SIMO NTST 2010

I took the Singapore IMO National Team Selection Test yesterday and today. It was like the IMO format i.e. 3 questions to be done in 4.5 hrs each day. The type of questions were: 1. Geometry, 2. Algebra, 3. Combinatorics, 4. Combinatorics, 5. Number Theory, 6. Inequalities. They were taken from the IMO 2009 Shortlist questions (in the IMO, there are Longlist questions and Shortlist questions, and the 6 questions for IMO are selected from the Shortlist questions). I am not supposed to reveal the questions as some other countries may also be using some of these Shortlist questions which were not selected for IMO questions, for their own national selection tests.

Too bad there was only 1 Geometry qn, usually in the IMO there are 2, one for each day. Anyway, I could only solve qn 1, 2, 4, 5 and 6. I think the ever pro Ivan could solve all 6 questions!

*note: this is in fact the 2nd selection test. The 1st selection test with a lower weightage was held about a month ago.

Another Math Qn

Another question posted on the cbox:

A travelled from Town P to Q. B travelled from Town Q to P. They started at the same time. They met each other 80km from Q. When A reached Town Q, he immediately travelled back to Town P. When B reached Town P, he also immediately travelled back to Town Q. They met each other 60km from P. What was the distance from Town P to Town Q?

Solution (not drawn to scale) by Lim Li:

Qn from SMOPS 2010

Someone posted the following question from SMOPS 2010 in the cbox:

s=1/((1/2001)+(1/2002)+(1/2003)+(1/2004)+(1/2005)+(1/2006)+(1/2007)+(1/2008)+(1/2009)+(1/2010)). Find the largest whole number smaller than s.

Soln:
Clearly, 10/2001 > (1/2001)+(1/2002)+(1/2003)+(1/2004)+(1/2005)+(1/2006)+(1/2007)+(1/2008)+(1/2009)+(1/2010) > 10/2010
Hence 2001/10 < s < 2010/10
Therefore the largest whole number smaller than s is 200.

Excuse from Lessons & Mid Year Exams Coming

The 2010 SIMO National Team Selection test is here again. It will be held on 1 May (Sat, Labour Day where our brains have to labour much) and 2 May (Sun), the day we emo. I can skip as many lessons/test/quiz/exams/lectures as I want and get away with it :-). I think I will still be attending some lessons (e.g. science lectures/lab, computer programming lab which I like).

My school mid year exams will be from 30 April to 7 May. I will also be taking AP Calculus BC exam on 5 May. Yay, my principal gave me permission to be exempted from the English exam on 30 April :D

Ala Carte Buffet Dinner at Dragon Gate Restaurant

Yesterday was my paternal grandmother's birthday. We had ala carte buffet dinner at the Dragon Gate Restaurant. I was slightly late as I helped out at the NUS High Open House (Physics booth at the Concourse) till 4 pm, went home to change and then met my family at the Harbourfront Centre. The dinner was not that cheap, about $30 per person, and the food not really to my liking. I only liked fried man-tou, lobster ball, cheese beancurd, beancurd wrapped chicken and mixed fruit with sago dessert.

My paternal grandmother has 7 grandchildren.

My sisters and cousins watching me playing games on iphone (my uncle's, not mine - I don't even own a handphone).

My Self-Portrait

NJC Secondary Maths Challenge 2010

I took part in the NJC maths challenge yesterday. I met some people from the national training team - 4 from RI, 1 from RGS and 2 from HCI. I got first in individual and third in team, and also got 2 more prizes in the audience round. In total, I got 2 medals, 2 graphic calculators and 2 random prizes.

妈妈的感触

This post is written by my mother.

从妈妈的生病到她的逝世，我深深地体会到“人生不如意之事，常之八九”这句话的含义。一个人的一生中，不知要伤心欲绝和痛苦难耐多少次。我指的伤心事是，当亲人逝世（你能想象有几次吗？父母、叔伯婶姨、朋友、兄姐。。。）离你而去，指的痛苦事是，当你病入膏肓时身体的煎熬，而不是和朋友争吵、失去工作、考试不及格等的“芝麻绿豆”小事。

我想，如此的人生，难怪有些人需要精神寄托，也可能就是这个原因，才有那么多不同的宗教被发起。本来有宗教信仰是好的,只可惜，很多人用宗教的名义来干不道德的事，更可笑的是，有些人利用宗教杀了人后，还振振有词说“杀人是为了要警戒人们，杀人是不对的！”