First, plot the points.
(20, 5), (30, 10), (40, 15), (50, 20)
A. You'll see that it's a perfectly straight line, so it's a perfect positive correlation --- Positive because it increases from left to right. The value to represent this is 1. A correlation of 1 means time and distance have a perfect positive linear relationship, meaning if x increases by a certain value, y also increases by a certain value at the same time. In our case, every time x increases by 10, y increases by 5
The slope represents the rate (or speed). Distance, rate, and time are related by
distance = rate • time
distance / time = rate
rise / run = m
1/2 = m
It's a correlation because x and y are related by a common pattern
The car's speed is 1/2 miles per minute.
