In maths today, we completed an investigation into how subtraction is not commutative. We used counters, tens frames and dice to find as many different number sentences as we could, where we subtracted from numbers between 6 and 20! We also found that we could use the number facts to help identify another number sentence.
So, if we know that 20 – 5 = 15, then we also know that 20 – 15 = 5!
We were able to prove that subtraction is not commutative and we were able to use our knowledge of number facts to help identify different number sentences.
Well done Dahl.