Julie finds that the number of hours she sleeps each night is related to the scores she receives on quizzes the next day. As her sleep approaches 8 hours, her quiz scores improve; as her sleep drops to 5 hours, her quiz scores show a similar decline. Julie realizes that __________
A) there is a negative correlation between the number of hours she sleeps and her quiz grades.
B) there is a positive correlation between the number of hours she sleeps and her quiz grades.
C) her low quiz scores are caused by sleep deprivation the night before a quiz.
D) she should sleep about 10 hours a night to ensure 100 percent quiz grades.

Question

Quizplus · Accepted Answer

The description suggests a positive correlation between the number of hours of sleep and quiz scores, as increasing sleep leads to improving quiz scores and decreasing sleep leads to declining quiz scores. Option A, negative correlation is the opposite and option C, sleep deprivation being the cause of low quiz scores is not supported by the information given. Option D, sleeping 10 hours to ensure perfect quiz grades is not supported by the information given and is an extreme answer.

Julie Finds That the Number of Hours She Sleeps Each