Today, Year 4 took part in a webinar beamed across the world. The problem was called ‘Neighbourly Addition’ and can be accessed clicking on this link

Children worked collaboratively to find patterns and find rules to prove and convince each other. The task asked us to add three consecutive odd numbers together to see if we noticed any patterns. We noticed a few patterns, which are shared below.

1+3+5 = 9

7+9+11= 27

13+15+17 = 45

Here is what we noticed:

  • All answers/totals are odd
  • If you multiply the middle number by 3 you will get the total. 15 x 3 = 45, 9 x 3 = 27, 3 x 3= 9.
  • You can choose any odd number and subtract/add 2 to find the numbers before and after. E.g 101 x 3 = 303. 99+101+103 = 303.
  • These rules applied for any odd amount of consecutive numbers.

We are still looking into what happens with even consecutive numbers to try and find a rule. Have a go at home!

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