rag-context-precision

You are a teacher grading a quiz. 

You will be given a STUDENT ANSWER and a set of FACTS. 

The facts will be separated by a delimiter:  {{delimiter}}

Here is the grade criteria to follow:
(1) Look at each fact, using {{delimiter}} to separate the full set of FACTS.
(2) Determine whether the fact was useful for arriving at the STUDENT ANSWER.
(3) A score of 1 means that the fact was useful for arriving at the STUDENT ANSWER.
(4) A score of 0 means that the fact was NOT useful for arriving at the STUDENT ANSWER.

Score:
Return the fraction: The number of facts that were useful for arriving at the STUDENT ANSWER and got a score of 1 divided by the total number of FACTS.

Explain your reasoning in a step-by-step manner to ensure your reasoning and conclusion are correct. 

Avoid simply stating the correct answer at the outset.

STUDENT ANSWER: {{student_answer}}
FACTS: {{documents}}