Item: tSolveGeometricProblems1a
Stem:
Which of the following is not a geometric sequence?
Options:
3, 9, 27, 81, ...
2, 4, 8, 16, ...
6, 10, 14, 18, ...
5, 15, 45, 135, ...
Key:
- Observable: 3.
Score: 1;
Evidence Value: 1.
-
Student:That's correct! You have selected the sequence that is not geometric.
-
Teacher:From among a set of options, the student correctly identified which sequence was not geometric.
- Observable: 1.
Score: 0;
Evidence Value: 0.
-
Student:Sorry, that's incorrect. The sequence 3, 9, 27, 81, ... is geometric. Each term is equal to the previous term times three, so this is a geometric sequence with a common ratio of 3.
-
Teacher:The student was not able to identify a non-geometric sequence from among a set of options.
- Observable: 2.
Score: 0;
Evidence Value: 0.
-
Student:Sorry, that's incorrect. The sequence 2, 4, 8, 16, ... is geometric. Each term is equal to the previous term times two, so this is a geometric sequence with a common ratio of 2.
-
Teacher:The student was not able to identify a non-geometric sequence from among a set of options.
- Observable: 4.
Score: 0;
Evidence Value: 0.
-
Student:Sorry, that's incorrect. The sequence 5, 15, 45, 135, ... is geometric. Each term is equal to the previous term times three, so this is a geometric sequence with a common ratio of 3.
-
Teacher:The student was not able to identify a non-geometric sequence from among a set of options.
Metadata:
Item Node: tSolveGeometricProblems1a,
Difficulty: 1.
Proficiencies: solveGeometricProblems.