standard_description: Recognize that a measure of center for a numerical data set summarizes all of its values with a single number, while a measure of variation describes how its values vary with a single number.
problem_activity: Task
To compute the perimeter of a rectangle you add the length, $l$ and width, $w$ and double this sum.
Write an expression for the perimeter of a rectangle.
Use the expression to ﬁnd the perimeter of a rectangle with length 30 and width 75.


aligns: no