Answer key

The answer, and what a wrong answer means.

#	Problem	Answer	If they wrote…
1	4 + 9	13	14 rounding to add, then forgetting to adjust
2	9 + 8	17	18 rounding to add, then forgetting to adjust
3	3 + 3	6	no pattern to catch here
4	3 + 1	4	no pattern to catch here
5	5 + 6	11	no pattern to catch here
6	4 + 5	9	no pattern to catch here
7	8 + 7	15	no pattern to catch here
8	8 + 6	14	16 rounding to add, then forgetting to adjust
9	5 + 5	10	no pattern to catch here
10	7 + 5	12	no pattern to catch here
11	8 + 5	13	15 rounding to add, then forgetting to adjust
12	7 + 7	14	no pattern to catch here
13	6 + 5	11	no pattern to catch here
14	6 + 3	9	no pattern to catch here
15	7 + 7	14	no pattern to catch here
16	7 + 6	13	no pattern to catch here
17	5 + 1	6	no pattern to catch here
18	9 + 7	16	17 rounding to add, then forgetting to adjust
19	6 + 9	15	16 rounding to add, then forgetting to adjust
20	9 + 9	18	no pattern to catch here

Reading the wrong answers

One wrong answer is a slip. The same pattern on three or more problems is a rule your child is following, and it has a name and a fix. Problems marked "no pattern to catch" are the plain ones; a child who gets only those right is telling you something too.

Reading the wrong answers

Rounding to add, then forgetting to adjust 6 of 20 problems