This post is part of a series outlining No More Marking’s initial findings from a mathematics research project, carried out jointly with Axiom Maths, in 2023-2024.
"Once again, the student is approaching fully correct answers, although technically, the first question is not quite correct (some of the examples, e.g. 9 + 9 + 6, did not use different single digits)."
This just seems flat-out wrong to me. The original problem statement did not require the digits to be different; instead, it only required that the 3-digit numbers are distinct:
"The digits of the 3-digit whole number 384 add up to 3 + 8 + 4 = 15. How many different 3-digit whole numbers can you find whose digits add up to 24?"
So 9 + 9 + 6 is in fact a perfectly valid solution to this problem.
Hi Theodore, thank you for the comment and it is a fair observation. When we designed the question we did have in mind that the numbers be distinct and on reflection we could have made that clearer. I don't think that impacts on the comparative judgement but that lack of clarity is something we do recognise.
"Once again, the student is approaching fully correct answers, although technically, the first question is not quite correct (some of the examples, e.g. 9 + 9 + 6, did not use different single digits)."
This just seems flat-out wrong to me. The original problem statement did not require the digits to be different; instead, it only required that the 3-digit numbers are distinct:
"The digits of the 3-digit whole number 384 add up to 3 + 8 + 4 = 15. How many different 3-digit whole numbers can you find whose digits add up to 24?"
So 9 + 9 + 6 is in fact a perfectly valid solution to this problem.
I have amended that as I agree, that is confusing.
Hi Theodore, thank you for the comment and it is a fair observation. When we designed the question we did have in mind that the numbers be distinct and on reflection we could have made that clearer. I don't think that impacts on the comparative judgement but that lack of clarity is something we do recognise.