SMO 2017 Junior Round 2 List
Cut off for Rd 2 ~16
SMO 2017 Junior Questions
SMO 2017 Junior solutions by a group of Year 1 students from NUS High is here
You can find past year SMO papers (2005-2013, Round 1 and 2 with full solutions) here.
For more SMO Junior Special Round practice, you may download the All Soviet Union Math Competition 1961-1987 here (note that only the first 99 questions have solutions included).
SMO 2017 (Junior Section) Answers
1. A
2. E
3. D
4. A
5. D
6. A
7. B
8. C
9. C
10. B
11. 7 (assuming interior angles are integers)
12. 277
13. 22
14. 85
15. 1
16. 18
17. 2017
18. 10
19. 49
20. 1144
21. 2
22. 71
23. 24
24. 1442
25. 4033
26. 61
27. 18
28. 677
29. 5
30. 16
31. 2016
32. 2
33. 79
34. 60
35. 8
Qn 2 should be E.
ReplyDeleteAgreed, q2 should be E
ReplyDeleteQ2 is e and is getting 27 questions correct a bad thing?
ReplyDelete27 questions? Wow I'm so impressed!!!
ReplyDeleteCan anyone help explain why qn 8 is c
ReplyDeleteQuestion 21 should be 4
ReplyDeleteQ21
ReplyDeletehttp://www.wolframalpha.com/input/?i=(x%5E2-((x%2B1)%2F2)%5E2)%2F(((x%2B1)%2F2)%5E2-1)%3D(sqrt(3)%2B1)%2F(3-sqrt(3))
AD/BC=3+2sqrt(3)
http://www.wolframalpha.com/input/?i=(4%2B2sqrt(3))%2F(3%2B2sqrt(3))*sqrt(3)
Q8
ReplyDelete5,17,19
5,5,5
17,17,17
19,19,19
5,17,17
5,19,19
17,19,19
19,17,17
total:8
LL, 5,5,5 and 17,17,17 are congruent, hence counted as one.
DeleteAns =10 where you can extend the length using one or more rods. Taking in mind restrictions of only once.
is 16 a good mark
ReplyDeleteSUBSTITUDE X = -1
Deleteq20 should be 1068
ReplyDeleteQ20) a = 13, b = 1, c = 88
ReplyDeletea^2 + bc = 169 + 88 = 257
ab + bc = 13 + 88 = 101
Thus, abc = 13 × 88 = 1144 and NOT 1068.
yes 21 should be 4
ReplyDeleteHow do you do qn 17? ... I got 2019 + 2*sqrt(2017)
ReplyDeleteWhat do your think is the cut off point for round 2 this year?
ReplyDelete14
DeleteHow to do Q16
ReplyDeleteHow many marks is needed for bronze based on previous years?
ReplyDeleteHow much is needed to score honorable mention this year? Is 5 enough?
ReplyDeleteIs 5 to 6 enough for honorable mention?
ReplyDeleteI dun think so. based on previous years is 6 and this year's paper is easier
ReplyDeleteWait could someone explain q8
ReplyDeleteCould someone help me with Q16
ReplyDeleteWhy isn't q8 E? And why isn't q4 C?
ReplyDeleteWhy isn't q4 C and q8 E?
ReplyDeleteShould number 25 be 4035 instead?
ReplyDeleteNo. For Q25, the inequality holds when x ranges from -2015 to 2017 (including 0) so there are 4033 solutions
DeleteShouldn't question 13 be 27?
ReplyDelete1+4+4+8+9+22=6×8
DeleteThis comment has been removed by the author.
ReplyDeleteAgreed.That was my reasoning too
ReplyDeleteI realised that 15 is the cut off for last year smo junior round 2 based on the comments in last year's post. With a score of 14 for round 1, will i be able to make it into round 2?
ReplyDeletePossibly, but this year's paper was easier than last year. There is a chance though
ReplyDeleteWhat will i get if i get around 6 to 7?Will i be able to get honourable mention?
ReplyDeleteDepends. Most of time 7 to 8 should give honorable
ReplyDeleteFor Q14 I made a calculation error:
ReplyDeletesqrt 5 × sqrt 5 =25
So I got 425 :(
Also, Q8 is C
ReplyDeleteBecause 5 5 17 and 5 5 19 doesn't work
So the answer is 10-2
And I put 58 for Q34 because I forgot that 35/175, 70/175 .... 140/175 repeated.
ReplyDeleteso is q8 C or E?
ReplyDeleteHow much is needed for silver based on previous years?Around 12 to 13?
ReplyDeleteCould someone help explain question 25? Thanks.
ReplyDeleteFor Q25
ReplyDeletex^2+2015x+1<2017x+2017^2
x^2-2x+1-2017^2<0
x^2-2x-(2016)(2018)<0
(x-2018)(x+2016)<0
I can't explain this next part but you can visualise it as a quadratic graph with equation y=(x-2018)(x+2016) which is a u-shaped quadratic graph (opening upwards) with roots 2018 and -2016. There will be a region of the graph below the x axis which satisfies
(x-2018)(x+2016)<0. If you draw it out yourself you get this:
-2016<x<2018
So integers -2015 to 2017 satisfy the inequality and the number of integers is 2017+2015+1=4033. Take note that the inequality is not inclusive (a.k.a -2016 and 2018 are not included)
Hopefully this helped because I'm honestly not that great at explaining these type of questions.
@SMO noob From my explanation above 5,5,17 and 5,5,19 do not work so the answer for Q8 is 10-2=8 (C)
@anonymous your explanation sounds good!You must have did pretty well in Smo.How much did you get?
ReplyDeleteI should start giving myself a username :)
ReplyDeleteI didn't record all my answers but from what I recorded I got 22...could have gotten higher if I didn't make careless mistakes on Q14 and Q34.
@smo guy wow!You confirm second round
ReplyDeleteWhat school are you btw?
@anonymous
ReplyDeleteI'll probably just say I'm not from NUS High, school doesn't really matter :)
What can 13 get me?I know it probably won't take me to second round but can i get silver or bronze?
ReplyDeleteIs 22 or 23 enough to get a Gold?
ReplyDeleteYou can enter second round and probably have to get a few marks there to boost your chances of getting gold
ReplyDeleteProbably a gold and if you do well in round 2, you may even get into SIMO team.
ReplyDeletewhat is usually cut-off for silver?
ReplyDeletewhat can 16 get me
ReplyDeleteA silver maybe?
ReplyDeleteIs it possible to get silver without going second round?
ReplyDeleteYes it ia possible but you have to score like 1 or 2 mark below the cut off for round 2 i think.
ReplyDeleteHi! We're students from NUS High M17106 and we know that some of you might require solutions.
ReplyDeleteSolutions are not in Popular or any other bookstore, so we're here to provide you with them.
http://nushs-smo-junior-2017-sol.blogspot.sg
Here's a link to get to the solutions.
Hello, I am from Vietnam. It is surprising for me to go to Singapo for round 2 of SMO. But now,I don't have any document& exam to learn.I hope you will help me and upload the exams of SMO for me.Sorry, because my English is not good.Thank you so much.
ReplyDeleteAll the world: 10% (500/5000)
ReplyDeleteVietnam: 55% (76/139)
Impressive, right :))
Kim Oanh, download past year papers (2005-2013 both Rd 1 and 2) from below:
ReplyDeletehttps://www.intereseducation.com/resources/smo-problems-with-answers-and-solutions-singapore-mathematical-olympiad/
So is question 8 C or E?
ReplyDeleteNg Bee Yong, thank you very much.
ReplyDeleteHeard that the 2nd round results are out.
ReplyDeleteAnyone knows what is the cut-off points?
Where are the second round results posted
ReplyDeleteI heard from teacher
ReplyDeletethe results are not out
ReplyDeletei checked the singapore maths society website
Guys the results are out!!!
ReplyDeletehttp://sms.math.nus.edu.sg/Competitions/SMO2017/SMO%20Junior%20R2.pdf
ReplyDeleteWhat is cut-off?
16 got me in!
ReplyDeleteWill we be able to know if we got silver, bronze or honorable mention?
ReplyDeleteAfter the second round. The results for gold, silver, bronze, etc will be shown together
ReplyDeleteThanks for your reply!!
Delete16 got me to second round
ReplyDeleteAnyone got lower than 16 still went second round?
ReplyDeleteif we get into round 2 will we get gold (if we do badly for r2)
ReplyDeleteNo.Silver
ReplyDeleteok thank you
ReplyDelete@Anon how much did you get to go round 2?
ReplyDeleteWhat is the cut-off point to get into round 2 this year?
ReplyDeleteLets say cut-off is 16. If i get 14, do i still stand a chance of getting silver?
ReplyDeleteYes should be
Deleteif i do not attend round 2 will i get at least silver
ReplyDeletei got 16
ReplyDeleteYes.Anyone who got 15 can share whether they got into second round?
ReplyDeleteare all of students who got away to round 2, attend or no, certainly got medal?
ReplyDeleteYou would get definitely a silver at least if you go to round2.
ReplyDeleteso cutoff is 16?
ReplyDeleteFor the second round, is each question worth only 1 mark?
ReplyDeleteFor round 2, each question is worth 10 marks. However, solutions are required.
ReplyDeleteIs listing or guess and check allowed for round 2
ReplyDeleteCan you teach me how to do question 13 please
ReplyDelete