Sign Up!
Login
Welcome to Test-paper.info
Sunday, February 19 2017 @ 03:10 PM CST
 Forum Index >  Test Paper Related >  Primary 5 Matters
 p5 maths problem sum
   |  Printable Version
By: lisatang (offline)  Tuesday, April 24 2012 @ 10:52 AM CDT (Read 1611 times)  
lisatang

Dear all

May I check is there a better or shorter way to solve this question?

Forum Junior
Junior

Registered: 01/26/12
Posts: 19

Profile Email    
   
By: MathIzzzFun (offline)  Tuesday, April 24 2012 @ 05:26 PM CDT  
MathIzzzFun

Quote by: lisatang

Dear all

May I check is there a better or shorter way to solve this question?



Hi

this is a triangular pattern.
Pattern 1 = 1
Pattern 2 = 1 + 2
Pattern 3 = 1+2+3
Pattern N = 1+ 2+3+4+ ...+N = N (N+1)/2
Pattern 48 = 48 x 49 /2

cheers.

Forum Chatty
Chatty

Registered: 04/02/10
Posts: 36

Profile Email    
   
By: lisatang (offline)  Thursday, April 26 2012 @ 11:24 PM CDT  
lisatang

Hi

Thanks for your help but does primary school student know this?

regards
lisa

Forum Junior
Junior

Registered: 01/26/12
Posts: 19

Profile Email    
   
By: MathIzzzFun (offline)  Sunday, April 29 2012 @ 11:06 PM CDT  
MathIzzzFun

Quote by: lisatang

Hi

Thanks for your help but does primary school student know this?

regards
lisa



Hi

the students are taught how to add 1+2+3+4.... N, but may not be taught the general formula ie N(N+1)/2 - students learned this in maths olympiad training though.
However, G&C are taught so students can use the "look for pattern" heuristics see that the sum is N(N+1)/2 eg. Pattern 1 = 1
Pattern 2 = 1+2 = 3 = 2x3/2, Pattern 3 = 1+2+3 = 6 = 3x4/2.. then using G&C, they can then get the final answer ie 48

cheers.

Forum Chatty
Chatty

Registered: 04/02/10
Posts: 36

Profile Email    
   


 All times are CST. The time is now 03:10 pm.
Normal Topic Normal Topic
Locked Topic Locked Topic
Sticky Topic Sticky Topic
New Post New Post
Sticky Topic w/ New Post Sticky Topic w/ New Post
Locked Topic w/ New Post Locked Topic w/ New Post
View Anonymous Posts 
Able to Post 
HTML Allowed 
Censored Content