Figure 5 contains some responses provided by Year 5, 6 and 7 students which formed a benchmark
sample for a score of 4, 3 or 2 for this question:
Score 4
A Year 6 student, having completed the statement, 7 + n − 1 = 1 + n + 5, said:
“This answer is correct because you will always get an answer 6 more than n, because n less 1
plus 7 will give us 6 more than n. Also because n more than 5 plus 1 will give 6 more than n. This
will have a lot of different answers but you will always get an answer 6 more than n.”
A Year 7 student wrote n − 1 + 7 = n + 5 + 1, and explained:
“My answer is correct as no matter what n is, n − 1 is 6 units less than n + 5. This is balanced as 7 is
six units more than 1.”
Score 3
A Year 7 student wrote n − 1 + 7 = n + 5 + 1, and wrote:
“7 and n − 1 become 6; n + 5 and 1 become 6. Both sides are equivalent to 6”.
Score 2
A Year 5 student wrote 1 + n + 5 = 7 + n − 1, and then let n = 5 showing that
1 + 5 + 5 = 7 + 5 − 1. No reason was offered to show why the statement is always true.