Amelia tossed a paper cup 10 times. The cup lands either on its side, on its base or on its top. The data below shows how the cup landed each time.

Step A

If Amanda tosses the cup now, what is the probability that it will land on its side? Express your answer as a decimal.

Step B

Explain how you determined your answer. Use what you know about probability in your explanation. Use words, numbers, and/or symbols in your explanation.

Step A is scored 0 (Incorrect) or 1 (Correct) and assesses 5.B.1.b.
Step B is scored with a 3 point (0, 1, 2) rubric and assesses Processes of Mathematics.

Answer Annotation

Step A Answer: 0.6

Step B Sample correct response: Since the cup landed on its side six out of ten times in the experiment, the probability that it will land on its side now is six out of ten. Six out of ten expressed as a decimal is 0.6.

Score 2

The response demonstrates a complete understanding and analysis of a problem.

• Application of a reasonable strategy in the context of the problem is indicated.
• Explanation¹ of and/or justification² for the mathematical process(es) used to solve a problem is clear, developed, and logical.
• Connections and/or extensions made within mathematics or outside of mathematics are clear.
• Supportive information and/or numbers are provided as appropriate. ³

Score 1

The response demonstrates a minimal understanding and analysis of a problem.

• Partial application of a strategy in the context of the problem is indicated.
• Explanation¹ of and/or justification² for the mathematical process(es) used to solve a problem is partially developed, logically flawed, or missing.
• Connections and/or extensions made within mathematics or outside of mathematics are partial or overly general, or flawed.
• Supportive information and/or numbers may or may not be provided as appropriate.³

Score 0

The response is completely incorrect, irrelevant to the problem, or missing.⁴

Note 1:

Explanation refers to students' ability to communicate how they arrived at the solution for an item using the language of mathematics.

Note 2:

Justification refers to students' ability to support the reasoning used to solve a problem, or to demonstrate why the solution is correct using mathematical concepts and principles.

Note 3:

Students need to complete rubric criteria for explanation, justification, connections and/or extensions as cued for in a given problem.

Note 4:

Merely an exact copy or paraphrase of the problem will receive a score of "0".

Rubric Document Date: August 2003