Customers Arrive at the Local Grocery Store at a Steady

question 49

Multiple Choice

Customers arrive at the local grocery store at a steady rate of 40 an hour. Thirty percent of these customers purchase 10 items or less and go to the express line where they enjoy an average checkout time of 5 minutes. Customers that don't meet the express line criterion go to checkout line #2 where they spend an average of 10 minutes checking out. How many people are checking out in both lines on average?

• A) less than or equal to 1.0
• B) greater than 1.0 but less than or equal to 3.0
• C) greater than 3.0 but less than or equal to 5.0
• D) greater than 5.0

---

Definitions:

Correlation

Usually a number between +1.0 and -1.0 that indicates whether and how much two variables are related. Correlation indicates whether an increase in one variable will increase or decrease another variable. Correlation indicates only that two variables are somehow related, not that one variable causes the other to increase or decrease.

Variables

Elements or factors that can change and affect the outcome of experiments or studies, often manipulated or measured by researchers.

Causal Link

The relationship between two events where one is the result of the occurrence of the other; a cause-effect relationship.

Dependent Variable

In an experiment, the variable that may change as a result of the independent variable (whatever new condition the experimenter adds). In other words, the dependent variable depends on the independent variable.