Item: tTableExtendArithmetic1a
Stimulus:
| A |
B |
| 2 |
5 |
| 3 |
7 |
| 4 |
9 |
| 5 |
11 |
| ... |
... |
| 7 |
? |
Stem:
If the pattern shown in the table on the left were continued, what number
would appear in the box at the bottom of column B, where A is 7?
Options:
19
13
18
12
15
Key:
- Observable: 1.
Score: 0;
Evidence Value: 0.
-
Student:Sorry, that's not right. In problems like this, you need to find
the common difference and add it to the last given number the right
number of times. The common difference here is 2, and the correct
answer is 15.
-
Teacher:Could be that the student added wrong.
- Observable: 2.
Score: 0;
Evidence Value: 0.
-
Student:Good try, but not quite. It looks like you added the correct common
difference (2) to the last given item only one time. The problem asked
for the value of B when A is 7. The correct answer is 15.
-
Teacher:Could have added 2 to the "last number" ignoring the hiatus.
- Observable: 3.
Score: 0;
Evidence Value: 0.
-
Student:Sorry, that's not right. In problems like this, you need to find
the common difference and add it to the last given number the right
number of times. The common difference here is 2, and the correct
answer is 15.
-
Teacher:Seems to have added 11 to 7.
- Observable: 4.
Score: 0;
Evidence Value: 0.
-
Student:Sorry, that's not right. In problems like this, you need to find
the common difference and add it to the last given number the right
number of times. The common difference here is 2, and the correct
answer is 15.
-
Teacher:It's possible that the student just added 1 to 11.
- Observable: 5.
Score: 1;
Evidence Value: 1.
-
Student:Right!
-
Teacher:The student got this item correct.
Metadata:
Item Node: tTableExtendArithmetic1a,
Difficulty: 1.
Proficiencies: TableArithmetic,
ExtendArithmetic.