Copyright © University of Cambridge. All rights reserved.

'Odd Times Even' printed from http://nrich.maths.org/

Show menu

We had just a few solutions sent in from pupils trying to give some kind of proof for this challenge. Jasmine
  from Salcombe Prep. 
School in London sent in this picture and wrote:

 

Every time the numbers will make a rectangle

 

and from Michelle at the International School in the Seychelles we were sent the following:


When you multiply an even and an odd together it will always be an even number and when you times even and even togther it will also be an even number and how I did this was with cubes and I showed my teacher and he agreed with me.

 

Chris
 from St. Mary's Catholic Primary,
 England
 had a good way of showing it:


An odd number multiplied by an even number will make an even number. 
Key: different colour = different number


 

Finally from Christopher and Rei
 at Seoul Foreign School (SFS)
, South Korea (Republic of Korea) we have the following:


Answer for Odd Times Even:
For example:
4*3=12  that's the same as 4+4+4
4 is even.
Everytime an even is added to a even the answer is always a even number.

We hope that we convinced you that an odd number times an even number is always an even number.

 

Thank you for all the contributions.  It obviously made you think - and thinking is good!