Y-y(1) = m(x - x(1))
y - 1 = (-3/4)(x + 8)
The measure of central tendency give you a picture of what to expect in a situation. For example, a basketball players average is the amount of points that they typical score.
In a business, you make decisions on what you expect to happen. Knowing the measure of center can help you make better decisions.
The 30 inch ribbon is longer because the 2 foot ribbon is 24 inches long because 2 feet is 24 inches because there is 12 inches in a foot. Therefore, the 30 inch ribbon is longer because 30 is greater than 24.