## Search found 9 matches

Tue Feb 02, 2016 10:51 pm
Forum: Secondary Schools - Academic Support
Topic: Lower Secondary Mathematics
Replies: 346
Views: 87906

### Re: Lower Secondary Mathematics

Lisa_Love wrote:does 2^2 mean 2*2?
2^2 means 2 square
2^4 means 2 to the power of 4
Mon Feb 01, 2016 3:20 pm
Forum: Secondary Schools - Academic Support
Topic: Lower Secondary Mathematics
Replies: 346
Views: 87906

### Re: Lower Secondary Mathematics

The HCF of 2 numbers is 4, and their LCM is 240. What are the numbers? Is the answer simply 4 and 240? How do I show it in working? No, there are more possibilities HCF=4=(2^2) LCM = 240=(2^4)*3*5 Let the two integers be A,B So it means one integer should have two number of 2s, the other integer sh...
Wed Jan 27, 2016 2:58 pm
Forum: Secondary Schools - Academic Support
Topic: Lower Secondary Mathematics
Replies: 346
Views: 87906

### Re: Lower Secondary Mathematics

Can someone help my ds on this? The LCM of 6, 12 & n is 660. Find all possible values of n. 6 = 2 * 3 12=2² * 3 660 = 2² * 3 * 5 * 11 n must include 5 * 11 n = 5 * 11 = 55 n = 2 * 5 * 11 = 110 n = 2² * 5 * 11 = 220 n = 3 * 5 * 11 = 165 n = 2 * 3 * 5 * 11 = 330 n = 2² * 3 * 5 * 11 = 660 Can someone ...
Mon Nov 16, 2015 10:46 pm
Forum: Secondary Schools - Academic Support
Topic: O-Level Additional Math
Replies: 1807
Views: 284331

### Re: O-Level Additional Math

Volcano123 wrote:can someone help me with this questions
q13(ii) and Q14.
Thank you
Where is the questions?
Tue Feb 04, 2014 3:43 pm
Forum: Mathematics
Topic: All About Math Olympiad Training & Questions
Replies: 2375
Views: 613375

### Re: Sharing Math Olympiad Qns

One way is to write out all numbers until it start to repeat. The period is 71+23=94 (though maybe a factor of it). However, this way is not recommended due to its tediousness. 2nd way, T2 mod (94) has the same remainder regardless of adding 71 or -23. Same for T3, T4,... Tn. Therefore T2013 mod (94...
Wed Oct 30, 2013 11:05 pm
Forum: Mathematics
Topic: All About Math Olympiad Training & Questions
Replies: 2375
Views: 613375

### Re: Sharing Math Olympiad Qns

A qn designed by me, roughly SMO difficulty.
A sequence starts from 1 as 1st term. For subsequent terms, if Tn < 100, then
T(n+1)=Tn+71. If Tn≥100,then T(n+1)=Tn-23.Find T2013.
Mon Oct 21, 2013 11:57 pm
Forum: Mathematics
Topic: All About Math Olympiad Training & Questions
Replies: 2375
Views: 613375

### Re: Sharing Math Olympiad Qns

For Q2. The following scores are possible 0,3,5,6,8,9...,32 Starting from 8, every number can appear. Therefore the only scores that are not possible to occur are 1,2,4,7. The idea is to find all combinations without any restrictions first, subtract the number of combinations having either 1,2,4,7. ...
Sat Oct 19, 2013 10:55 am
Forum: Mathematics
Topic: All About Math Olympiad Training & Questions
Replies: 2375
Views: 613375

### Re: Sharing Math Olympiad Qns

For Q1, 3n+5 is not a multiple of 3 5n+4 is not a multiple of 5 So highest common factor of 3n+5 and 5n+4 is same as highest common factor of (3n+5)*5 and 5n+4 = highest common factor of (3n+5)*5 and (5n+4)*3= highest common factor of 15n+25 and 15n+12 Note that if A is a multiple of C and B is also...
Thu Oct 17, 2013 11:24 pm
Forum: Mathematics
Topic: All About Math Olympiad Training & Questions
Replies: 2375
Views: 613375

### Sharing Math Olympiad Qns

Hope to promote sharing and discussion of Math Olym questions. Two questions from a recent China Math Competition for P6. Quite challenging for Pri students and I gave to my RI GEP student from my Sec 1 Math Olympiad class instead. Q1) n is an integer <50. Find all possible n such that 3n+5 and 5n+4...