Item: tTableModelExplicitOtherRecursive3a
Stimulus:
The cost to rent a motorbike is given by the following formula:
Cost = ($3 x number of hours) + $2
| Time in Hours |
Cost in Dollars |
| 1 |
5 |
| 4 |
A |
| B |
17 |
Stem:
Fill in the values below for A and B from the table.
Inputs:
- Enter the value for A: $
- Enter the value for B:
hours
Key:
- Observable: 14,
5.
Score: 1;
Evidence Value: 1.
-
Student:Your answers, $14 and 5 hours, are correct. Good job!
-
Teacher:The student got this item correct.
- Observable: 5,
14.
Score: 0;
Evidence Value: 0.
-
Student:Sorry, that's not right.
You entered the correct values, but in reverse order.
The correct answers are $14 and 5 hours.
-
Teacher:The student may not have read the question carefully.
- Observable: 14,
53.
Score: 0;
Evidence Value: 0.
-
Student:Sorry, that's incorrect. You calculated the value for A correctly.
But B is not calculated using the same formula.
In order to calculate the value for B, you should first subtract,
and then divide.
The correct answers are $14 and 5 hours.
-
Teacher:Looks like the student applied the same formula to calculate both A and B. The student may not understand to apply inverse operations in reverse order for B.
- Observable: 14,
.
Score: 0;
Evidence Value: 0.
-
Student:Sorry, that's not right. You need to fill in both empty cells
in the table.
The correct answers are $14 and 5 hours.
-
Teacher:Student didn't fill in both cells.
- Observable: ,
5.
Score: 0;
Evidence Value: 0.
-
Student:Sorry, that's not right. You need to fill in both empty cells
in the table.
The correct answers are $14 and 5 hours.
-
Teacher:Student didn't fill in both cells.
- Observable: 18,
3.67.
Score: 0;
Evidence Value: 0.
-
Student:Sorry, that's incorrect. You may have misapplied the order of operations.
To calculate A, first multiply, and then add. To calculate B, first
subtract, and then divide. Remember that in calculating A, you should
do the operation in parentheses first.
The correct answers are $14 and 5 hours.
-
Teacher:The student does not understand the use of parentheses,
and may also be confused about the order of operations.
- Observable: 14,
3.67.
Score: 0;
Evidence Value: 0.
-
Student:Sorry, that's incorrect. Your answer for A is correct, but you may have
misapplied the order of operations when you found B. To find B, you
should subtract before you divide.
The correct answers are $14 and 5 hours.
-
Teacher:The student divided before subtracting when calculating the value for B.
- Observable: .
Score: 0;
Evidence Value: 0.
-
Student:Sorry, that's incorrect. Here's how to calculate the value for A: 4 hours
multiplied by $3 per hour is $12. $12 plus $2 equals $14. To get B,
apply inverse operations in reverse: first subtract $2, and then divide
by $3 per hour.
The correct answers are $14 and 5 hours.
-
Teacher:Not sure what the problem is.
Metadata:
Item Node: tTableModelExplicitOtherRecursive3a,
Difficulty: 3.
Proficiencies: ExplicitOtherRecursive,
TableOtherRecursive,
ModelOtherRecursive.